Rothco ECWCS Gen III Mid-Weight Underwear Bottoms (Level II)

Powerful Insulation: Get ready to tackle the cold with our ECWCS Gen III Level II Underwear Bottoms. Made from breathable, mid-weight grid fleece material that is great for layering, the thermal base layer military underwear is designed to keep you warm, comfortable, and dry, even in the harshest winter weather.
Stay Warm & Dry: The base layer pants wick sweat and moisture away for optimum comfort, swiftly transferring it to the top layer for a quick dry. This allows you to move freely without your clothing sticking to you, ideal for winter operations, hiking, camping, skiing, snowboarding, hunting, and other outdoor activities.
Comfortable Fit: Built from a soft polyester / spandex blend, the grid fleece fabric easily flexes and contorts with your body for optimum comfort. The base layer pants feature an access fly, along with an elastic waist and leg bottoms that help insulate your body heat.
Active-Duty Approved: The thermal bottoms are part of the Extended Cold Weather Clothing System (ECWCS) and are a must-have for any military personnel, tactical professional, or outdoor enthusiast in cold climates. Whether you are gearing up for a mission or camping up in the mountains, you will want to keep a pair on you.
Better Together: Stay warm and comfortable this winter with our matching ECWCS Gen III Level II Underwear Tops. The base layer shirt features the same breathable, mid-weight grid fleece material as the bottoms, ensuring that you’re ready for the mission at hand.


Durable fabrics designed for comfort, performance, and long-term wear.
Inclusive sizing and tailored options to help you find the perfect fit without compromise.
Get your uniforms delivered quickly — because we know you can't wait weeks.
Order exactly what you need — no bulk requirements or confusing minimums.
Every piece is carefully inspected to meet high standards before it reaches you.
Wherever you are in the U.S., we ship directly to your door with care.

Durable fabrics designed for comfort, performance, and long-term wear.

Inclusive sizing and tailored options to help you find the perfect fit without compromise.

Get your uniforms delivered quickly — because we know you can't wait weeks.

Order exactly what you need — no bulk requirements or confusing minimums.

Every piece is carefully inspected to meet high standards before it reaches you.

Wherever you are in the U.S., we ship directly to your door with care.

Request A Quote