The MA-1 Slim Fit has a flight nylon, water-resistant shell with nylon lining and 100% polyester fill. The bomber has two flap pockets with snap closures, two interior welt pockets and Alpha s signature zippered utility/pencil pocket on the sleeve with the red "Remove Before Flight" tag. Features knit collar, cuffs and waistband. *Sizes listed are in Mens Sizing. This style of MA-1 flight jacket is a slim fit, if you don't want a slim fit then you may prefer to purchase a size larger in this style or choose the Blood Chit Style Bomber which is more true to size. PRODUCT HISTORY: Introduced by the mid-1950s, the MA-1 became the flight jacket of U.S. Air Force and Navy pilots and ground crew. Designed for use in temperatures of 14-50 degrees F, the MA-1 had a 100% wool knit collar, waistband and cuffs. The MA-1 discarded the mouton fur collar of its predecessor, the B-15, because it interfered with the parachute harness worn by aviators. Other features of the jacket included a tab that the oxygen mask was clipped to, tabs to hold the headset wires in place and the original U.S. Air Force decal. These features were eventually removed from the flight jacket as it was adopted by other branches of the U.S. Armed Forces and equipment for pilots changed. An addition to the jacket in 1960 was the reversibility to show off an Indian Orange lining. The reason being if a plane crashed, the pilot could reverse the jacket to the orange side to signal rescue personnel. Alpha Industries' first government contract for the MA-1 was awarded in 1963. They started producing the MA-1 flight jacket for the civilian population in the 1970s. Black was added to the military sage green requirement. The jacket has evolved over the years but it is still has the DNA of the classic flight jacket.