1. What is bulletproof plates? A bulletproof plate — also called an armor plate, ballistic plate or trauma plate — is inserted into a bullet proof vest to provide additional protection for the wearer. 2. What is the level of the ballisitc plates? There are losts of standard in the world including GA standard from China, NIJ stadnard from USA, HOSDB from UK, VPAM from Germany, Gost from Russia and etc. But the most used international standard in the world is set by National Institute of Justice (short for NIJ) of the United States Department of Justice, which currently has five threat levels, and each one is classified by the caliber of bullet it can stop. The five threat levels are: Level IIA Level II Level IIIA Level III Level IV   3. What is the difference of hard or soft armor? There are two main classifications of bulletproof plates. There's hard armor, which is made from heavier and sturdier materials, and soft armor, which uses thinner and lighter materials. While levels IIA, II and IIIA are regularlly made of soft armor, III and IV are hard plates. 4. Different types of the plate cuts Full cut: This has a rectangular or square shape and provides full back protection. Shooter's cut: This has a rectangular shape and cut-off corners, providing better movement and agility for shooting. Swimmer's cut: This resembles the shooter's cut, but more of the top area is removed for additional shoulder and upper back movement. SAPI: This stands for “small arms protective insert.” A SAPI usually weighs three to five pounds and is preferred by military personnel.