Maximus Plus1 Followers for Ruger® MK Series Magazines (2-PACK)- Replacement magazine followers that increase magazine capacity from 10 rounds to 11 rounds. The TANDEMKROSS “Maximus” Plus1 Follower for the Ruger® MK series is a drop-in upgrade that makes your gun competition ready - whether you're shooting a Ruger® MKIV, MKIII, MKII or 22/45. The “Maximus” Plus1 Follower allows the user to load 11 rounds into a standard 10-round magazine - ideal for rimfire competitions, which allow the shooter to start with 11 rounds. The follower is made of durable Zytel® and is bright red, improving safety by showing the shooter when the magazine is empty. Package contains two (2) magazine followers.- Installation is Easy: Disassemble your Ruger MK Series magazine. Then, re-assemble it again only replace the factory follower with the Maximus Plus1 follower.