U.S. Military Original OD Green Cold Weather Helmet LinerU. S. Military Original OD Green Cold Weather Helmet Liner These cold weather helmet liners were first issued in the early 1960s to troops station in cold weather areas. Sateen style OD green fabric outer base, and wool synthetic inter material. To be originally warn under the standard M1 helmet, these liners can also be warn standalone as a "hood" or configured to an "ushanka" look. Great Condition Various dates and manufacturers. Late 1970s dates to