S.T. Action Pro Inert Safety Trainer Cartridge Dummy Ammunition Ammo Shell Rounds with Nickel Case - Pack of 10 (Orange, 9mm) VISIBLE - metal case with orange ABS plastic insert makes the round highly visible INERT - completely safe, dummy rounds used for training and instructional activities TRAINING - classroom training, loading/reloading drills, gun handling drills, malfunction drills and diagnosing shooting problems NICKEL CASE - no chance of rim breakage RECESSED PRIMER HOLE - prevents damage to your firing pin