HEXAMAG's AR-15 4-Slot Low Profile M-Lok Rail Covers (4 Pack) add a unique look to your handguard and protect your investment. With their high-performance"" non-slip design"" these rail covers not only look amazing but they function better than others on the market and complete your rifle's ability to get the job done. The M-Lok rail covers use the patented WedgeLok technology to hold it securely to your hand-guard. When installing simply press each section firmly into each M-Lok slot. Once the WedgeLok is in place it will expand and lock in behind the hand-guard.