M1941 Knit Cap to be worn under the Helmet in cold conditions. Often called the Jeep Cap or the Radar cap after being constantly worn by Radar O'Reilly in the TV series M*A*S*H.
The M41 Jeep cap was issued from 1942 to all US troops in WW2. These are made in the correct WW2 OD#3 green colour and has the six stitch starfish pattern on the top crown, modern jeep caps are a darker green and have a four stitch pattern.
This knitted cap was designed to give warmth and padding/comfort when wearing the M1 steel helmet.