The OD cotton field cap with visor was designed to be worn with the M-1943 field jacket. It could also be worn under the hood of that jacket and with the steel helmet and liner.
The OD pile field cap was designed for wear in extreme cold.
The MQ-1 (Model Quartermaster 1) OD pile field cap is a modified version of the M-1943 pile field cap. The cap was adopted as the M-1951 pile field cap.
The M-1951 field cap was designed for ground troop wear in a range of cold-wet to hot environments and is a lightweight windproof item incorporating a very thin layer of insulation only in the earlaps.
The M-1951 pile field cap may be worn for both cold-dry and cold-wet conditions. The cap provides the best protection against the elements for weather colder than 0°F.
The M-65 cold weather insulating helmet liner cap is worn alone or as a liner for the helmet assembly. The earflaps are fasten under or over chin, at back of neck, or are folded up around the top with the touch-and-close fasteners crisscrossed in the front.
The hardface micro fleece cap is intended for wear by male and female military personnel of the USMC in mountainous and cold weather environments.It will provide improved wind resistance, durability and water repellency when worn in intermediate to cold weather environments.It will be part of the Mountain/Cold Weather Clothing System and will ultimately replace/phase out the current micro fleece caps.
The knitted wool watch cap is intended for wear by Naval and Air Force personnel in cold environments.
The cap is intended for wear as multi-purpose lightweight head protection.
Commercial item description A-A-50369 covers the requirements for a Cap, Knit (Watch) used by Navy personnel in cold environments.
Commercial item description A-A-59453 covers the requirements for a synthetic microfleece cap that is used as multi-purpose lightweight head protection.
Military specification MIL-C-16472 covers the requirements for a knitted wool watch cap.
Military specification MIL-C-1911 covers a cap made from cotton and nylon with flannel lined earlaps.
Military specification MIL-C-1913 covers a cotton poplin, field cap with wool pile lined earflaps.
Military specification MIL-C-43549 covers a fully lined insulating helmet liner cap with adjustable forehead flap.