JT 90g CO2 Cartidges (88g Crosman AirSource cylinders compatible) Compatible with any air rifle or paintball marker that accepts 88g cartridges. Approx .5" longer than Crosman 88g AirSource cylinders. Seller has personally tested in Hammerli 850, Gamo Extreme and QB79 rifles with excellent results. Remember to always apply a drop of airgun oil to tip of cylinder and on threads.