Adjustable Bore Guide - AR-10 .308 Caliber - Should be used when cleaning a Bolt Action Rifle - Protect bore throat - Aircraft grade anodized aluminum - Sleeve pin is brass - Superior Delrin Bore GuideSpecifications:Model: Bore GuideWidth: 1.4Length: 13.2Height: 1.2Weight: 0.6Bristle Type: NoneMaterial: DelrinProtects: Bore During CleaningSeries: 308/762mmSimilar Items: CLRODSize: 308/7.62 NATOSuitable For: 7.62mm RiflesType: Bore Guide