Christie's Mag Caps fit all high capacity magazines plus the factory magazines made for the Ruger 10/22. The Mag Caps fit over the end of your magazines keeping them clean when not in use. The Mag Caps protect the lips of the magazine from damage. If you keep a spare magazine in your pocket it will be clean and ready to go. There's no wrong way to put the Mag caps on. They fit tightly in either direction, with a virtual waterproof seal, but are easily removed. Made from santoprene thermoplastic rubber, they are flexible and tough. Sold in sets of two.