Military Clothing Systems

Over the past decade, we've finally been seeing the military take notice and adopt some of the advanced technology/high performance fabrics and clothing that civilian mountaineers and backpackers have been using for quite a while. Lighter, more compressible, breathable, quick drying and wicking fabrics now clothe the soldier, doing their part to make a tough job a bit more efficient and a bit less uncomfortable. Clothing the soldier presents a unique challenge as temperatures in certain regions may range greatly over a 24 hour period, or missions might start off at low altitudes and end up much higher. Soldiers most often have to be self-sufficient, carrying everything in their rucks and on their person, so light weight and clothing versatility rank high in importance. Unlike most sporting events, the soldier might have to wear the same clothing for days or weeks on end, and subject them to abuse that civilian use won't.
There are quite a few different clothing development programs out there, and it can be confusing. Since I have no personal knowledge on the subject, I've summarized some of the info from Polartec® literature and other sources like the U.S. Army programs website. I've given credit to the sources of information where possible, and if there's any violation of website policies, webmasters please let me know. Polartec® manufactures much of this high-performance material, and their website is a wealth of information, so please visit it for details. This list is by no means all-inclusive - there are a LOT more programs out there, but I've chosen those that are relevant for this website.

2/13/05 - Insport is a well known manufacturer of well designed and high quality athletic clothing which has been around for quite a while; I remember buying Insport cycling apparel when I was bike racing at the collegiate level, more than 15 years ago. Relatively recently, Insport landed a contract to produce clothing for the U.S. Navy, and shown here are a few items from their military line (which is available for purchase to civilians).

NS21 PCU Level 1 Lightweight Pant (below) - The Level 1 lightweight pant is constructed of Polartec® Power Dry® fabric with X-STATIC® in coyote brown. Intended to be worn next-to-skin as a base layer, the fabric is a wicking material, designed to keep your skin dry when you sweat. It's a bi-component knit that uses different yarns on either side of the fabric. Look at the photos above and you can see the inner surface which is optimized to move moisture away from the skin, and the outer surface, for fast drying. X-STATIC® inhibits the growth of odor-causing bacteria in the fabric, and incorporates pure silver-bonded fiber that is permanantly knit into the fabric construction and will last as long as the fabric does.
The pant has a comfort fit - not too loose and not skin tight like some undergarments. Personally, I prefer the looser fit to one that is skin tight. I like the feel of the Power Dry fabric, which feels more like a natural fiber than a synthetic. I dislike the synthetic feel of some popular tight fitting undergarments. The pant has an elastic waist band (a bit tight around my 32" waist, but it could loosen with use) and front fly opening. It's extremely lightweight and comfortable to move around in. I went running in these in low-60° weather, and they kept my legs warm enough until I warmed up but didn't feel overheated as I was running. After cooling down and I was pouring sweat, they dried fast whereas my cotton briefs were soaked with perspiration for a while.

NS82 PCU Level 2 Long Sleeve Midweight Tee (below) - Also meant to be worn next-to-skin, the Midweight Tee is constructed of Polartec® Power Dry® with 'Comfort stretch and voided construction' (sometimes referred to as 'R1' fleece, used by Patagonia's R2 jacket). Immediately noticeable when handling the Tee is the grid pattern in the lightweight fleece on the inside surface. The grid pattern serves to trap air in the void for warmth while reducing bulk for more compressibility than standard fleece. More for less - that's a great idea. It also feels very comfortable against the skin.
Styled like an undergarment, the Tee is cut slightly long (with the back being slightly longer), so it won't come untucked. Non-fleece X-STATIC panels run up each side, under the arms, and down to the cuffs, for odor protection and heat dissipation where it's most effective (like pit zips). A front zipper opens down to the sternum, which really helps regulate the temperature and ventilation. The medium height collar has a small tab in front for full fleece coverage and comfort at the top under the zipper.
I wore the Tee under my Level 5 Soft shell in the rain, and the Tee worked great as an underlayer without being too bulky under the shell. The Tee is warmer than a garment of comparable weight and bulk, so it's a bit surprising when you first put it on, but it's thin enough not to overheat like the thicker fleece garments might. The X-STATIC panels really help to reduce bulk where it's not needed and to keep you from perspiring under the arms.

Level 2 Tee and Level 1 Pant

Level 2 Tee

Rear view

Inner surface of tee, showing Power Dry and Thermagrid fabrics

Outer surface of Power Dry and Thermagrid fabrics

Details of tee

Front details of Pant

NS83 PCU Level 3 Half Zip Pullover (below) - The level 3 pullover is mainly constructed of Polartec® Thermal Pro® fabric, which is a family of fabrics with a variety of patterns and textures. The fabric used by Insport is an extremely high-loft material which has the highest warmth-to-weight ratio of the Polartec fabrics. Like the Thermagrid R1 fabric, it makes use of minute pockets of air space to keep the person warm and increase evaporation of perpiration. As seen in the above photo, the outer surface of the Thermal Pro has a diamond-pattern of small tufts of fibers. The inside has a soft, fuzzy, shearling-like texture.
The pullover has an athletic/medium fit, which might be a bit tight for the stockier fellows, so take that into account when choosing the correct size. It's amazingly light weight, and noticeably warmer than the Level 2 tee. The long 12" front zipper closes the 2" tall R1 Thermagrid-lined collar. The slightly lower loft Thermagrid fabric is used in the side panels, which extend up to the armpits. On the top of each wrist is a R1 thermagrid panel. I haven't been able to find out the 'official' purpose of this panel, but it makes pulling back the cuff to check your wristwatch easier as it's less bulky than the thicker Thermal Pro fabric. Maybe that's what it's for. The rear of the pullover is cut a bit longer for tucking into the pants.
Unlike the Level 2 tee, which looks like the undergarment that it is, the Level 3 pullover looks pretty darn good when worn as outer wear. Be aware, however, that the high-loft fabric with open-grid air spaces is not wind resistant (air passes freely through the fabric) and the pullover depends on a soft shell or windshirt to retain the trapped air. Worn alone, it's warm as long as there's no breeze. Donning the Level 5 shell over it immediately traps the warm air and increases the temperature. If it gets too hot, the shell can be removed - the beauty of the layering system.

Level 3 Half-zip pullover

Rear view

Collar fully zipped

Close up of collar area

Thermal Pro and Thermagrid textures

2/27/05 - STEPS Inc., produces the PCU Level 3 Half-zip pullover shown below. It's constructed of another high-loft/low weight variation of Polartec® Thermal Pro® fabric. Rather than having a visible grid-like pattern, it's a smoother, furry, texture, with a bit more density. The inside and outside surfaces are identical. The pullover is constructed almost entirely of Thermal Pro, except for Polartec Power Dry® Thermagrid fabric panel under the armpit.
It has a more generous cut than the Insport garment, being longer in both torso and sleeves (see photos for comparison) and looser in girth. Which you prefer obviously depends on your physical measurements. The rear of the pullover is slightly longer than the front. The 15" heavy duty front zipper with pull tab closes the 3" tall collar, which is double-thickness Thermal Pro. The denser fabric and lack of thermagrid side panels makes it slightly warmer than the Insport Level 3, and retains a bit more heat when worn alone as an outer garment (at the cost of slightly more bulk, also due to the more generous cut). While being a bit more resistant to wind, it's still most effective when worn under a windshirt or soft shell.

STEPS Level 3 pullover with collar closed

Front partially unzipped

Rear view

Detail of collar area

Close-up of under-arm thermagrid panel

STEPS thermal pro fabric

3/2/05 - SEKRI stands for South Eastern Kentucky Rehabilitation Industries and is a "non-profit organization whose primary purpose is to provide qualified personnel, facilities and related services for persons with disabilities, enabling them to obtain and to be successful in maintaining competitive employment". SEKRI manufactures Levels 1 (bottom wicking layer), 2 (added warmth) and 7 (water/wind resistant high loft insulated) garments of the SOF-PCU multi-layered cold weather system. All items are can be ordered directly from SEKRI online here.

PCU Level 1 T-shirt and Boxer- The Level 1 Silkweight T-shirt and boxer are constructed of smooth Polartec® Power Dry® fabric. Designed to keep your skin dry when you perspire, the stretch material has a smooth texture that feels very soft next to the skin. Depending on the light, the material (and most of these other PCU materials) can look "bronzine/gray-green" (as described on the SEKRI website) under fluorescent lights to a coyote-ish brown under natural and incandescent lighting. The medium size T-shirt was a perfect fit for me and cut very comfortably - no binding or restrictions; neither too tight nor loose. It's cut longer in the back than in the front, which seems to be common feature amongst the PCU garments.
The silkweight Boxer short is made of the same wicking material. I've worn the T-shirt to the gym and went running in it, and the difference between it and a cotton T-shirt is very noticeable once I start to sweat. It doesn't feel 'heavy' or clammy, and dries much, much faster. When doing laundry, I took some of the Power Dry fabric garments out of the washer along with similar cotton items, and let them dry naturally instead of throwing them in the dryer. The Power Dry garments were dry long before the cottom ones, which stayed damp for a long time.

Level 1 T-shirt front

Level 1 T-shirt rear

Level 1 Boxer front

Level 1 Boxer rear

PCU Level 1 Long Sleeve Shirt and Pant- Also meant to be worn next-to-skin, the Level 1 Long Sleeve Shirt and Pant are made of the same Polartec® Power Dry® fabric with X-STATIC® I've already covered in the Insport review above. Rather than the silky fabric of the T-shrt and Boxer, it has minute holes in the outside surface that aids in evaporation of moisture. A 12" zip in the front closes the 2.5" high collar. Also cut longer in the back, it'll stay tucked in.
The Level 1 Pant varies from the Insport product by having a wider middle gusset, and slightly looser plush waistband. Overall fit on me is about the same. It has a front fly opening. I can't stress how comfy these items are to wear. They're a perfect balance for when it's too cool for shorts and a short-sleeved t-shirt, but not cold enough for sweats.

Level 1 Long-sleeved shirt and Pant

Pant waist band

PCU Level 2 Gridded Fleece Long Sleeve Shirt and Pant - For additional warmth, the Level 2 Long Sleeve Shirt and Pant are made of the Polartec® Power Dry Fleece with comfort stretch and voided construction "R1" type material with the grid pattern on the inside. The fleece grid is visible through the smoother outer surface of the fabric and is most noticeable when you hold it up to the light. Again, depending on the light, it can look greenish, or coyote brown (see the pics above - the rightmost photo is taken under fluorescent lighting).
Unlike the Insport Level 2 Tee (same item, different nomenclature) which has Power Dry X-Static panels on the sides and arms, the SEKRI Shirt is constructed entirely of R1 fleece, so it is a bit warmer. Which one is preferable depends entirely on whether you need the additional insulation. The long, 14" front zipper opens to the bottom of the chest for temperature control. The 2.5" collar is an inch taller than the Insport's. The overall fit is looser, and it's also about an inch longer in length in the torso (the back is longer than the front).
The matching Level 2 Pant is also entirely constructed in R1 fleece, and has a fly opening. The gusset provides a lot of room and the waist comes up pretty high (there's quite a bit of overlap between the shirt and the pants). Again, these garments are warm for their weight, and the gridded fleece ensures that there's some airflow between the material and the skin to aid in movement of moisture vapour, meaning you stay drier.

Level 2 Long sleeved shirt and Level 2 Pant

Level 2 Shirt

Details of Level 2 Pant

PCU Level 7 Loft Garments - Level 7 is the warmest of the PCU clothes, meant for extreme conditions. SEKRI's Level 7 Loft garments are fully insulated, water and wind resistant, breathable and washable. The shell is constructed of the same lightweight alpha green/grey EPIC® nylon (called 'Praetorian', a 2.8oz fabric) by Nextec, as the Orc Ind. Level 5 soft shell. Nextec uses their encapsulation process to encapsulate the individual fibers of the fabric with silicone-based polymers to provide all-weather protection without coatings or laminates. Note that Epic® Nylon is water resistant, not 100% water proof. For use in wet conditions, the Level 6 Wet weather suit is recommended to be worn over the Level 7.
The garment linings are quilted and insulated with Primaloft® 5 oz. Sport fibers. Primaloft was developed for the U.S. Military as a filling for sleeping bags and clothing. It is a down-like insulation that has the lightweight compressibility and warmth of down, but also works when wet, as Primaloft's individual fibers are water repellent. Primaloft is highly compressible but quick to regain its loft. Primaloft Sport uses ultra-fine and multi-diameter fibers for water resistance and retention of loft, resulting in a water resistant, breathable, fast-drying and lightweight filling.

PCU Level 7 Loft Jacket - The SEKRI Loft jacket shown below is of a medium-length, hooded parka design. The front zipper is a YKK water resistant coil type with plastic splash guard. The removable zip-off hood is also fully insulated and quilted, with an elastic shock cord opening adjustment. It attaches behind the 3" tall collar. Both the jacket and hood are lined with soft, ripstop nylon material. On the front are two slanted slash pockets, with water-resistant zipper closures. The pocket openings are further protected by a flap to prevent water from dripping into them. The sleeves have elasticized cuffs. Inside the jacket are two large mesh pockets. The bottom of the jacket hem can be tightened around the hips with the elastic shock cord drawstring. The tops of the shoulders have Epic 'Glacier' (5.8 oz) non-swish material patches for abrasion resistance when wearing a pack.

Level 7 Loft Jacket

Side and rear views

Hood removed and showing front slash pockets

Inside of jacket showing mesh pocket

PCU Level 7 Loft Pant and Vest - The matching Level 7 Pant is also completely constructed of Epic® Nylon with Primaloft Sport insulation. It has a zipper fly and heavy duty snap waist. The waist is elasticized but also has velcro tabs on each side for adjustment. The pants don't have any pockets. The sides of the legs can be fully zipped open (actually, completely unzipped at the top), for ease of donning or a bit of ventilation if partially opened. The pant legs are pre-curved at the knee to better match the anatomy of the leg and bend more easily. The bottom of the pant leg cuffs are elasticized and have a velcro tab that protects the zipper.
The Loft Vest is a simple half-zip pullover design. The 14" zipper opens wide enough that donning and doffing isn't difficult, but I inquired about SEKRI making a full zipper opening design to increase versatility, which they're looking at. The vest is worn to keep the body core warm, if the extra bulk of the Loft Jacket can't be carried or isn't needed. There is a single, slanted opening, mesh-lined pocket over the left chest.

Level 7 Loft pant showing side zipper

Front and Rear views

Level 7 Loft vest

Collar open

Rear view

These garments are surprisingly easy to move in, despite their loft. I would have thought them to be more restrictive than they are. One minor nitpick (and it applies in general to most smooth nylon garments, not just these) is that they Epic® Nylon fabric is 'swishy' (might be because they're new) and might be of a concern to those who need stealth. The sound is most apparent when the inside of the thighs rub past each other when walking. On the shoulders of the jacket are two panels of Nextec® Glacier fabric that are different from the rest of the Epic® Nylon. It's a less 'swishy' sounding material. If SEKRI put a panel on the inside of each leg, from the crotch to the bottom of the knees, I believe this would really help in alleviating the noise. The 'swish' is a problem common to most smooth synthetic materials; that's why hunters wear silent fleece clothing when hunting.

Despite their 'loft', these garments compress quite nicely (one of the main features of the Primaloft® Sport insulation). I was quite surprised to find that I was able to stuff both the jacket with hood, and pant into the Kifaru back pouch shown below. The whole suit can be carried attached to the outside of your pack in a relatively compact package.

The jacket and pant will stuff into...

...a Kifaru back pouch