This bulletproof shield is laser cut off AR500 steel plates and welded with steel tube handle and arm rest. AR500 steel plate can withstand multiple shoots without structure failure like composite material. The 4mm (5/32") version is a Level II that stops up to 9 mm pistol shoots. The 6 mm (1/4"+) version is Level IIIA that stops pistol and rifle shoots from .38ACP, 9mm, .40 S&W , 10mm, up to 45 ACP. Sizes, Dimensions and Weights M: 20" x 12" 4mm, 10 lb M: 20" x 12" 6mm, 16 lb L: 22" x 12" 6mm, 17 lb XL: 22" x 14" 6mm, 20 lb XXL: 24" x 15" 6mm, 24 lb We made these in our shop for our family and friends, and now we made more for sale. We think this is very useful in situation that you need to pull out a gun to meet an intruder in a hurry.