spring power would drive the mechanism, firing a series of up to ten caps from a sprocket-fed roll. It was made initially for a Dick Tracy line of toys, then camouflaged for a Green Beret Guerilla Fighter line of weapons, then restyled again as a tie-in with the Planet of the Apes franchise. Types of caps Roll caps, perforated roll caps: often sold in sets of five rolls of 50 red paper caps per roll. Greenie Stick-M-Caps: Green peel-and-stick paper caps manufactured by the Mattel company to stick on the back of their "Shootin' Shells" Plastic, red circular discs used today. Containing gunpowder and a zinc alloy used to create a smaller explosion than would be previously reached with pure gunpowder components in the 1950s Plastic strips, similar to disks, but arranged in a line, often with means of attaching singular strips to one another Types of cap guns Ring cap guns are usually modeled after revolver pistols, with the cap ring placed in the cylinder section of the toy gun. Like its real-world counterpart, when the trigger is pulled, the cylinder rotates a new cap into place, the hammer is drawn back, and then released; the shock causes the cap to explode harmlessly, producing the noise and smoke. Strip or paper cap guns use the aforementioned cap strip in lieu of the cap ring. As in the ring style of gun, each pull of the trigger advances the cap strip forward, pulls back the hammer to the point where it releases, striking the cap. Potato or spud guns occasionally use a cap to provide a burst of gas to fire the projectile, a small cutting of potato. One design employs a small reusable metal "cartridge" which has a recess for a cap at one end and a small drilling through to the other end, which holds the potato. Due to the low energy contained in a paper cap and the poor seal around the cartridge, these spud guns usually have very modest range, barely enough to eject the potato cutting. Plug fire cap guns are almost exclusively from Japan and are more realistic in action often used by reenactors. they also fall under the category of Modelguns. Mattel introduced a modified type of roll cap that used sprocket feed instead of simple friction feed. Legal requirements Beginning in 1988, cap guns and other toy guns in the United States