Military Morons Pack page

Main Exterior features - The Arc'teryx LEAF packs I've featured on this site in the past have typically had a streamlined, minimalist exterior; and the DryPack 70 follows that trend. I'd reckon that a snag-free, smooth exterior is even more important for military use, especially if the Drypack 70 can be towed behind a swimmer. The Drypack 70 has both top and bottom grab handles. It doesn't have any side grab handles as the compression straps and RollTop securing straps can do double-duty as grab handles.

A 3-ft (1 m) removable tether for swimming or lowering is included with the DryPack 70, and is attached to the top grab handle, although it can be attached to the bottom one as well. It's a length of 1" webbing with loops sewn at both ends. The tether is folded up and stored at the top of the pack using two ITW Web Dominators. It's recommended that the tether is folded up in a zig-zag fashion, rather than just coiling it, so that a pull on the end can extend it without having to undo the Web Dominator keepers.

On the upper right side of the pack is the Oral Inflation Valve. This consists of an L-shaped tube with spring-loaded valve on the end, protected and secured by Velcro one-wrap sewn to the top of the pack. The valve allows for selective buoyancy for either surface assault swimming or sub-surface diving. The DryPack 70 can also be employed as an improvised flotation device for ground forces conducting a water obstacle crossing. The valve is used for purging or inflation, and is opened by depressing the mouth piece and closed by releasing it and allowing the spring to return it forward. The valve enables the user to add air (by blowing into it) or expel air (by squeezing the pack while the valve is open). There is a collar right below the mouth piece that is turned to lock it in the close position so that it cannot be depressed accidentally when not in use.

There are two removable, horizontal compression straps that are routed through the two channels on the front of the pack. The straps have a fold sewn into them on either side of the channel, which keeps them retained and centered. The straps are simply pulled out of the channel to remove them. To re-insert them, I used a long and thin screwdriver to push the end through the channel. Almost everything on the exterior of the DryPack 70 is removable (see the photos below) and the pack can function as a duffel bag. ITW Web Dominators are used to secure all loose webbing ends.

AC² Suspension System - The C² suspension system includes a laminated back panel; GridLock™ shoulder straps that adjust in width and height; removable Load Transfer™ Disc hip belt that rotates freely to stabilize load on uneven terrain. The removable suspension system was incorporated to allow for storage during administrative transport. Typically, the suspension system will be cinched down as the end-user requirement is to swim (insertion) to land, and be prepared to immediately don the pack if required to expeditiously move off the beach to the objective (infiltration).

The C² back panel provides the support and rigidity for the DryPack 70. It utilizes 420ACT fabric which has a bondable surface which allows lamination directly to the fabric, eliminating the need for traditional cut-and-sew manufacturing. The tri-laminate back panel is a composite of EVA foam, resilient Kydex plastic with dual extruded aluminum stays. It's thin and light weight; and as a unified structure, creates a curved shape and supportive form that creates a direct link between spine, suspension and pack.

Shoulder straps - The shoulder straps on the DryPack 70 are removable and use Arc'teryx's GridLock attachment system. The shoulder straps are anatomically shaped and taper from 3" wide at the top to 2" at the bottom. They are lightly padded with foam and backed with Tweave Durastretch fabric. The GridLock system has been around on Arc'teryx's commercial Alpine packs, and allows fine-tuning of the fit of the pack by adjusting the distance between the shoulder straps, and also their height relative to the pack (for shorter or taller torsos). The Gridlock system utilized a molded plastic panel that is bonded to the back of the pack frame. It has a 'grid' of keyhole-shaped slots - three rows and five columns. A small panel with three molded 'pegs' is attached to the shoulder strap. The pegs fit into the keyholes on the grid, and when slid upwards, lock into place.

Right below the grid panel are two fields of loop Velcro. Hook velcro fields are sewn to the back of the shoulder straps. The velcro keeps the straps from moving down, which keeps the pegs locked into the grid. To adjust the shoulder strap width or height, the strap is disengaged from the Velcro and pulled downwards, where the pegs can then be pulled out of the grid. The pegs can be moved up or down, left or right, and the Velcro re-secured. There's about 2" in width adjustment and 1.7" of vertical adjustment. It's easy and very quick to use. Ideally, the anchor points for the shoulder straps should be between the shoulder blades.

The sternum strap, as well as the shoulder straps, utilize the National Molding 1" Tether Pull buckle. They can be released the conventional way by squeezing the sides in, or by pulling on the cord-attached T-pull. They require a pretty deliberate tug and I doubt that they'll snag and release accidentally. If you're worried about it, the cord pull can always be removed. The DryPack 70 has a mixture of National Molding/Duraflex and ITW Ghilletex plastic hardware, and their side-release buckles are cross-compatible in this case.

The sternum strap is adjustable in height but not removable. The shoulder straps can be removed by disengaging them from the GridLock panel and undoing the 3/4" load-lifter straps at the top. The load lifters are there to slightly lift the shoulder straps from the shoulders, not to pull the top of the pack towards the back, and require only minimal tension to do their job.

Hip belt - The removable hip belt allows the end-user to use the DryPack with or without a hip belt. The hip belt is lower profile (less padded and stiff) than the A2² hip belts seen on Arc'teryx's commercial packs like the Naos, Altra and Arrakis. It is anatomically shaped with grooves in the foam to prevent creases.

The DryPack 70 utilizes the AC² rotating Load Transfer Disc which rotates freely to stabilize the load on uneven terrain The Load Transfer Disc is an interface between the hip belt and lower back of the pack. It acts as a pivot point; allowing the hip belt to rotate relative to the pack. When you bend or lean to the side at the waist, the pack moves with your body while the hip belt stays in place on your hips. The effect of this is that the pack feels less constraining when moving around (scrambling, bending, etc).

The Load Transfer Disc has two parts; one affixed to the back of the pack, and the other to the hip belt. Since this is a moving interface, the Disc comes pre-lubricated at the factory. Under normal civilian (mild to moderate) use, the Disc will not require any maintenance. However, military use of the DryPack 70 will most likely dictate a simple cleaning and lubrication of the Disc after prolonged use or exposure to surface contaminants such as sand, mud, or brush.

The hip belt is removed by loosening the side load stabilizer straps and un-threading them from the plastic buckles on pack body. With the DryPack 70 on its front on a level surface, the hip belt is rotated 1/4 turn counter-clockwise until Discs disengage with a small 'pop', and separate easily with minimal resistance. Once removed, both Discs can be wiped with a clean dry rag until debris is removed. If enough lubricant is remaining, the hip belt can be re-installed. If too much grit or debris remains, rag soaked with mild dish soap and warm water can be used to wipe the Discs, or toothbrush used gently to remove all debris. I was able to use a garden hose to remove all the sand that had accumulated in the Discs. A small quantity of AC² lubricant is then applied to the outer rings of both Discs and to interlocking lugs, being careful not to over-lubricate.

The hip belt is re-assembled in reverse. The pack is laid on its front on a level surface and the hip belt placed about 30° to the left (counter clockwise) and the teeth aligned on the Discs. Once aligned, firm pressure is applied on the face of the hip belt to press the Discs firmly together and then the hip belt is rotated clockwise until engaged. The hip belt's load stabilizer straps are re-threaded into the pack's plastic buckles. Note that a small sample of AC° lubricant comes with the pack in the internal pocket. Special AC² lubricant may be obtained from most Arc'teryx retailers. Alternately, plumber's silicone grease can be used as a back-up, available at most hardware stores or scuba dive shops. Oil based lubricants such as WD40 should not be used as it will cause the Discs to seize and degrade the urethane components.

RollTop Closure - Not surprisingly, the DryPack 70 has a RollTop closure, to ensure a water tight seal. Instead of the standard dry bag roll top closure that relies primarily on a tacky material at the entrance plus a number of folds to create the seal, the DryPack has a RF welded, 22" waterproof, German-made TIZIP MasterSeal 10 zipper as it's main seal. It's made from high-strength fabric coated with thermoplastic polyurethane. The extra strong plastic teeth are fixed on the top and bottom of the zipper tape. The zipper's coupling elements keep the sealing edges tightly sealed together when the zipper is closed. The slider is made from a salt water resistant metal. The slider movement is contact-free and does not wear on the zipper tape or sealing edge. Some dry bags use a ziploc-type seal (like Watershed bags), but they're not as quite as quick/convenient as a zipper.

The RollTop closure is a redundancy measure that will ensure that the bag remains waterproof if the zipper becomes damaged, or in a situation where the end user does not fully close the zipper. It also protects the zipper from dirt, debris and abrasion. A small tube of TIZIP lubricant is included with the pack; only the docking end needs to be lubricated as the chain is maintenance free. Sharp bending or twisting of the zipper should be avoided, and it should be kept closed for long and short term storage and transportation so that the closed chain can protect the sealing lips from dirt and damage. If dirt and sand do make it into the zipper mechanism, the zipper should be cleaned with soap and water. It's not a cheap component and the zipper alone retails for around $100.

The top has a buckle at each corner; male at one end and female at the other. When rolling the top over, it is folded over at least 4 times (I usually fold it 5 times) and the buckles secured to the side straps. I preferred to secure the top side compression straps over the roll top straps, rather than under them.

Interior - The DryPack 70 is a single-compartment patrol pack. The entire cavernous interior is lined in white, which makes it easier to find items inside under low light conditions. There's a 10" x 6" stretch fabric flat pocket just inside the top front of the compartment. All seams are taped and the inside is coated in urethane, just like the outside. The C² back panel provides the support and rigidity for the DryPack 70 and has two rows of webbing loops for strapping/securing contents. The webbing under the loops houses the aluminum stays, which are non-removable.

I was able to fit a FN SCAR-L rifle with stock folded inside the DryPack 70. Basically, anything the length of the back panel or shorter than 27" will fit in the pack. If it's longer, it will interfere with the RollTop closure, as the top of the pack is folded all the way down to the top of the back panel. Also visible from the inside is the Oral Inflation Valve port that leads to the outside of the pack.

Observations and notes - If a person wants to keep the contents of a pack protected from water, and also have a pack that has a proper suspension system from load carrying, they're usually limited to two options. The first is to have a regular patrol pack and put it inside a larger waterproof duffel or dry bag. The other is to put all the items inside smaller dry bags or plastic bags, then put them inside the pack. The issue with both of these options is added weight and complexity. The main purpose of the DryPack 70 is to combine the suspension of an Alpine pack and dry bag so that the end user has the lightest weight, most streamlined load carriage equipment for Maritime Special Operations.

The DryPack 70 is designed as a medium-sized patrol pack. It just looks large on me as I'm a little fellow (5' 7"). The urethane double-sided coated 725D material is stiffer than 1000D, and has a very abrasion-resistant feel to it. Until you get up close to the pack and see the TIZIP zipper, it's not apparent that it's anything more than a MultiCam Alpine-style pack. Upon closer examination, the Oral Inflation Valve, waterproof zipper and white urethane coating inside provide the clues to its intention.

As seen in the interior photos above, the inside of the DryPack 70 is one big compartment with no internal organization other than the flat zippered pocket. I mentioned above that the RollTop is folded over 4-5 times until it's limited by the internal frame sheet and the Oral Inflation Valve is on top. However, since the main barrier against water entering the pack is the TIZIP zipper, the RollTop can be folded over 3 times instead, to add more volume to the top of the pack, just like an extendable storm collar does on some packs. This adds a couple more inches to what you can fit inside it.

The TIZIP zipper and RollTop is very easy and quick to use; I can see why one would prefer it over most other dry bag opening arrangements. The Oral Inflation Valve works well for inflating or deflating the pack. Blow to add air and buoyancy; purge to get excess air out. I also found that I could 'vacuum pack' the contents of the DryPack 70 by sucking the air out of it. I had the top rolled down tight and the side compression straps tightened after I had squeezed out as much air as possible. I then proceeded to use the valve to suck more air out of the pack. This resulted in the pack forming around the contents better and giving the pack a really 'solid' feel as nothing could shift inside; just like when you handle something that has been vacuum packed.

I was familiar with the C² frame sheet, which is also present on the Khard Pack. It's thin, light weight and stiff enough to provide the structure and support for the pack. The GridLock shoulder strap system and Load Transfer Disc hip belt were new to me, though. The GridLock system is easy to adjust, and I really like having the ability to adjust the shoulder strap width and height. With the GridLock system, I'm able to adjust the take-off point of the straps to my liking, and utilize the load lifter straps correctly.

There was a little bit of confusion initially with the hip belt. The DryPack 70 User Manual said to rotate the hip belt clockwise to remove it. I tried and finally gave up as I didn't want to break it. Turns out that it needs to rotate counter-clockwise to remove it. The user manual should be corrected by time the DryPack 70 is available to the public. I can't think of too many reasons to remove the hip belt in the civilian world, except to clean and maintain the Load Transfer Disc mechanism. With the DryPack 70, the hip belt is intended to be removed and stowed for administrative transport or when the pack is worn over armour or with a battle belt. I used the pack without the hip belt installed, and while the Load Transfer Disc does bear against the lower back, I didn't find it uncomfortable because there isn't anything sharp poking out. What I'd like to see, however, is a simple Disc Cover with a thin pad that can be installed onto the Disc when the hip belt is not in use to protect the interface from potential damage and also to minimize the amount of debris filling up the rings.

When walking around and wearing the pack, I loaded it up for a total weight of 49.6 lbs. For the hip belt to offload weight to the hips, the hip belt needs to be tight around the hips. It's not supposed to be around the waist, but be centered on the iliac crests. The heavier the weight, the snugger it needs to be to prevent it from slipping down off the hips. One thing I'd like to see added is a couple of 2" loops added to either side of the belt, right where the 2" webbing connects to the padding. That way, the webbing end can be routed through it and allow the user to tighten the belt by pushing forward, where he has more leverage. As it is right now, I have to reach across the opposite side to get enough leverage to tighten the belt. Here's a retrofit to Mystery Ranch packs that does what I'm describing.

I took a series of short 2 mile walks around the neighbourhood to get a feel for the pack. loaded up. The hip belt, while not as luxuriously padded as the commercial versions, felt relatively comfortable. It was during these walks that I experimented with the different GridLock positions for the shoulder straps. Out in the desert, I did some walking on uneven terrain and scrambling up rocks, and that's where the advantages of the Load Transfer Disc became apparent. I liked the added mobility it gave me, as I no longer felt that my shoulders/torso were constrained from moving by the hip belt.

In the water - Since the DryPack 70 was conceived for use around or in water, this writeup wouldn't be complete without an attempt to get it wet. Luckily, I didn't have to resort to dunking it in the bathtub, running a hose over it or taking it into the shower as I live close to the ocean. It was a drizzly, cold, overcast day, which made it perfect for taking the DryPack 70 into the surf as we (my wife and 6-year old son were with me) were practically the only ones down on the beach save for the occasional beach jogger. I had the DryPack loaded up with about 30 lbs, which gave me a chance to experiment with changing the inflation/buoyancy. The surf was up that day, so the water was full of suspended sand to get into everything.

Since the suspension system is typically cinched down for the swim (insertion) to land, not removed entirely, I stowed the hip belt around to the front. I didn't bother with the shoulder straps as I wasn't about to actually go swimming and tow this thing behind me. With the pack fully inflated, I waded out into the surf to chest depth and let it float. It was very buoyant and could actually function as an improvised flotation device. I purged some of the air from the valve and was able to get it somewhat neutrally buoyant. The waves almost made me lose grip of the pack a couple of times, so I unrolled the tether and attached it to my wrist so I wouldn't accidentally lose the pack. I added more air back in and dragged it around in and out of the water, up and down the beach in the surf. I wanted to see how much the sand would affect stuff on the pack. I was in and out of the water for approximately half an hour, with the pack either floating or fully submerged, or sitting in the surf.

Once it was truly covered in sand, I took it for one last dunk in the water to rinse it off. I noticed a couple of things. Since the exterior of the pack is urethane coated, the fabric doesn't take on any water. Hence, it doesn't stay dripping wet for long. Most of the inital dripping came from the water-logged webbing. It doesn't get heavier from taking on water, and it dries very quickly.

Off the beach, I opened up the TIZIP and checked the contents of the pack. Bone dry. Not a drop inside, which was the expected result.

Stowing hip belt around the front

Unrolling tether

Dragging with tether

At home, I rinsed the pack off with a garden hose, and took off the shoulder straps and hip belt to see how much sand had made it into the GridLock and Load Transfer Disc mechanisms. As expected, there was sand in the mechanisms. It all easily rinsed out with the spray from the hose. There still seemed to be some lubrication left on the Disc mechanism even though all the sand had been washed out. I later re-assembled everything without adding more lubrication, to see if I'd experience any issues. I didn't, except that the Gridlock did creak slightly for a bit until I went on another long walk. I think that a small dab of lubrication on the Gridlock probably can't hurt until the new plastic wears in. There was no sand on the TIZIP zipper; the multiple folds of the RollTop kept any water or sand from reaching it.

I also noticed that the sand made the oral inflation valve feel gritty when pushing down on it. To clean it, I immersed the mouthpiece in a cup of water while actuating it (pushing it in and out), and a lot of sand came out. I also filled my mouth with water and blew it through the tube/valve from the inside of the pack where the port is, and that helped clean the rest of the sand out.

The DryPack 70 was designed and manufactured to meet the needs of particular military end-users. However, I don't think that its use is limited to military or special operations use. At first glance, the DryPack 70 might seem overbuilt for civilian use, but anyone working around water or in a wet environment (rainforest, rain, rivers etc) with a need for keeping the contents of a pack dry could probably put it to good use. Rain covers for packs just protect them from the elements, but don't do so well when submerged or dunked into streams or rivers. When crossing a river, this pack can be used as an improvised flotation device rather than something that can drag you under should you lose your footing. Dry bags keep stuff dry, but none are really suitable for humping loads for distances; they don't have proper suspension systems. When on a ship or boat, should your DryPack 70 go overboard, you'll know that the contents will be protected, and the pack will float (dependent on the weight and volume of the contents, and amount of airspace that can be filled with air).

If you need a water proof pack that also has a real alpine suspension system, it's the only game in town for now. It's going to be lighter and more convenient than any conventional alpine pack/dry bag combination, or packing individual items in waterproof bags inside a conventional pack. It's a niche item, and the price reflects that (and probably causes many civilians to suffer from sticker shock). Considering the cost of the equipment that it's meant to carry and protect, and the potential risk to a military mission or scientific expedition because of water-damaged equipment failure, it's a small price to pay for the benefits that it offers. Peace of mind - what's it worth to you?