With the Crosman Full Auto AK1 BB air rifle firing 1400 rounds per minute you might want to pick up a few of these AK1 Magazines! This extra mag spring feeds 25 BBs for rapid-fire action and houses two Powerlet CO2 cartridges. - Spring feeds 25 BBs for rapid-fire action - Holds two Powerlet CO2 cartridges - Compatible with the Crosman Full Auto AK1