The Viking AR500 Gong Plates are cut from certified AR/NMSOO steel, bead blasted and primed to make sure you get the highest quality gongs. The gongs are 1/2" thick plates for rounds up to 4500 FPE (at the target). If you have never shot steel gongs, You don't know the fun you are missing. Please follow industry safe practices with the use of any steel target and always wear ear and eye protection.