AR-STONER(TM) is now offering replacement components for the AR-15 that are made to strict military specifications. These high quality components will provide excellent fit and reliable function in your AR series platforms. These AR-STONER(TM) parts are perfect for upgrading existing components or replacing worn or broken parts. Don't waste your time or money on unreliable AR parts, grab a few of the AR-STONER(TM) parts today! Features4 Piece Kit1 Shim Is 1.5 Mm (.06")3 Shims Are .15mm (.0055")Helps With Timing Of Muzzle Device