HEXAMAG's AR-15 7-Slot KeyMod Low Profile Rail Covers (4 Pack)"" add a unique look to your handguard and protect your investment. They look amazing"" function better than others on the market and complete your rifle's ability to get the job done. SENTRY Keymod rail covers use the patented WedgeLok(R) technology to hold it securely to your hand-guard. When installing simply press each section firmly into each Keymod slot. Once the WedgeLok(R) is in place it will expand and lock in behind the hand-guard.