JPX 4 Inert Cartridge Full Case (12) 4 packsThe JPX 4 Inert practice canisters are a great option so you can gain experience using the JPX4 pepper gun should that day arrive you need to fire the OC Spray to be safe and escape danger. The Inert Practice package includes four shots of a mix of water dye formula. When the Inert Practice Cartridges are used, they do replicate you firing the OC Cartridges so you can have the safe degree of confidence using the PPX4 pepper gun. The JPX4 Inert