First Defense® X2 has all the industry-leading attributes of the original, but with twice the capsaicin concentration for extra pungency. It also uses the environmentally safe propellant, nitrogen. Choose from MK-3 or MK-4 sizes MK-3 contains 6 - 8 bursts of spray MK-4 contains 11 - 12 bursts of spray Effective Range: 10' - 12' Protective, spring-loaded safety cap Flip-top actuator assists in directional targeting and discharging Cover prevents accidental discharge No separate lifting motion is required to activate the device Specify: MK-3 (1.47 oz.) or MK-4 (3 oz.)