Gives the soldier a 40% saving throw against explosive weapons such as grenades or mines.
However, in giving a soldier this equipment, their bulk increases by 10. Obviously one must take into account this as they give Rangers their equipment as an extra 10 bulk may be crucial to fast moving roles, such as Rangers specializing in Spot, or Rangers using heavy weapons such as the M60 Machine Gun
Derived from the German term "Flugzeugabwehrkanone", the Flak Jacket - Flak being a general term for shrapnel - was a ballistic nylon or steel plated jacket designed to keep soldiers, airmen, sailors, and Marines safe from explosions and shell fragmentation. This was its primary role, and as such, it had a hard time protecting from the enemies bullets. It provided next to no protection against the Vietnamese weapons and could stop little more than a .45 handgun round, but did provide considerable projection against metal fragmentation and other explosive damage.
The U.S. Army's vests (classified as Body Armor, Fragmentation Protective, Vest M69) weighed under eight pounds and were made of several layers of ballistic nylon. The vests used by the U.S. Marines, however (designated as Vest, Armored M-1955) weighed more than ten pounds and were a combination of ballistic nylon layers and fiberglass plates. In modern times, almost all ballistic vests and flak jackets feature heavy Kevlar.