Due to the shortage of leather goods during World War II, the military introduced the B-10 jacket in 1943 to replace the B-6, A-2 and other fur jackets (the L-2 in 1945 was designed to replace the A2). and was launched in April 1944, The B-15 jacket replaces the B-10 jacket. In November of the same year, the B-15A version was launched. In August 1945, the B-15B was roll out. It is the world's first nylon flight jacket. On September 18, 1947, the air force is independent of US Army Air Force, The US Air Force was established. In 1950, the Air Force launched its own Air Force Blue Flight Jacket, the B-15C. The military logo on the Left arm was changed from USAAF to USAF. In 1953, the B-15D was launched, The color changes from dark blue to grayish green with better survivability, The B15 series is now complete. In the early post-war period, all the B-15 series retained the B-10-shaped large fur collar. With the entry into the jet era, the hard-flying helmet, which is completely different from the World War II leather flying Cap, described being widely equipped. The pilots then found that the sheared fur collar did not fit well with the new helmet and sometimes hindered the carrying and use of the pilot's umbrella. In 1954, the US Air Force Materials Department issued a directive requiring All stock B-15 jackets to be retrofitted. Change to a Small stand collar with the same material as the neckline hem. These modified models will be re-stitched with a white label on the original label, marked as "MOD" retrofit to indicate that This is a modified B-15 jacket. The B-15 (MODIFIED) series is the revised hairless collar jacket. The B-15 4 models have MOD variants. Does the B-10, which is its predecessor, also have a "MOD" type? If the Air Force Materials Department Has a B-10 inventory surplus, then the existence of this version is reasonable. Of course, this B-10 "MOD" is not real, and it belongs to an imaginary style.