Troy Standard AR-15 Barrel Nut. These Troy Industries AR 15 Parts are compatible with the standard nut and will work with most rail systems. In addition the Troy AR-15 Barrel Nut indexes easy with the gas tube for a tight seal every time. The Troy Standard Barrel Nut is a durable high-quality and affordable addition to your AR-15. Specifications for Troy Standard AR-15 Barrel Nut: Manufacturer: Troy Condition: New Country of Origin: USA Troy Barrel Nut OY-BAN-SRAI-BNT-0000-00 Compatible with the standard nut Indexes easily with the gas tube Package Contents: Troy Standard AR-15 Barrel Nut OY-BAN-SRAI-BNT-0000-00 Troy SRAI-BNT-0000-00: Standard AR-15 Barrel Nut