US Military ECWCS Light Weight Thermal Underwear

ECWCS Lightweight Base Layer

These are the thermal underwear bottoms from the US military's ECWCS, the Extended Cold Weather Clothing System. ECWCS is a set of garments worn in layers so a soldier can add or remove warmth as conditions change. This lightweight piece sits next to the skin as the first layer, under uniform trousers, insulated pants or shell pants. Hunters, backpackers, winter workers and anyone building a surplus cold-weather kit can use them the same way.

Features

• Genuine US Military Issue — Made for the US Army's cold-weather clothing system, not a commercial copy sold under a military name.
• ECWCS Lightweight Layer — This is the lightest, next-to-skin garment in the ECWCS layering system, designed to go on first with heavier layers added over it.
• Synthetic Fabric — The polyester-based fabric, with fleece and nylon listed in its makeup, dries faster than cotton long johns and holds less water against the skin.
• Elastic Waistband — A covered elastic band holds the bottoms in place without a drawstring or buttons, so nothing presses under a belt.
• Fly Front — An overlapping fly opening means you don't have to pull the layer down in the field.
• Close-Fitting Cut — Slim, tapered legs sit close to the body, so the bottoms slide under trousers without bunching at the knee.
• Finished Ankle Cuffs — Plain hemmed cuffs tuck neatly into socks or boots.
• Tan Colorway — A neutral desert tan shade matches other issue base layers and suits sand-toned uniforms.

Built For Layering

The lightweight ECWCS bottoms do one job: they are the thin first layer that every warmer layer goes on top of. Their close fit and plain construction leave room for a midweight layer, fleece or shell pants over them, which is how the system was meant to be worn. For collectors and reenactors filling out a US Army cold-weather loadout, this is the issue base layer that belongs at the bottom of the stack.