Blood chit is a small sheet of material depicting the flag of the issuing government and a statement in several languages to the effect that anyone assisting the bearer to safety will be rewarded. This is used by the military, usually aircraft personnel, which provides rapid identification and help to a downed flyer. This is also known as escape and identification flags in the U.S.
Modern blood chit belts are used by the U.S. soldiers in Afghanistan. These belts are made of heavy duty material.