Intended for close range defensive use. Load provides an option to lead or copper projectiles. Can be used as a painful warning shot but can also be lethal under some circumstances. Load also provides a greater margin of safety to innocent persons nearby or in adjoining rooms. Twin .60 caliber balls have relatively high velocity but have relatively low mass. Available kinetic energy is shed quickly over distance. Penetration of the body is possible at close range. Some level of injury should be expected and can range from serious injury or death to painful welts or bruising. Kinetic Energy at muzzle: 120ft/lbs Projectile Diameter: .60 caliber. Muzzle Velocity: 900fps in18 inch barrel. 5 rounds per box, 20 boxes per case.