Due to the ballistic filler (most frequently made of Kevlar), it provides protection against bullets
fired from small arms and grenade shrapnel.

There are 5 classes of body vests (IIA, II, IIIA, III, IV). The higher the class, the more effective protection of the life of the person wearing it is provided. There are several standards which describe ballistic penetration resistance of vests. Class IV vest (according to NIJ standard) corresponds to Class 5 of the German DIN standard or Class B7 of the European CEN standard.

Most frequently needed is vest Class IV; it protects the person against Caliber 7.62 mm armor-piercing bullets as well as bullets of lower velocity, such as cartridges fired from an automatic rifle AK47.