The Twistone Horse Pistol Gas Barrel is engineered for reliable performance with 5.56 NATO/.223 Remington chambering and a 7.5-inch barrel length featuring a 1:7 twist rate for optimal bullet stabilization.Twistone Horse Pistol Gas System Barrel (SKU: OH-BR07)7.5-inch barrel length5.56 NATO/.223 Remington chambering1:7 twist rate for heavy bullet stabilizationPistol-length gas systemDimensions: 1.35" x 4.05" x 8.80"Note: No direct shipping to CaliforniaIdeal for AR-15 pistol builds and short-barreled rifle applications this barrel delivers accurate performance in a compact configuration. Please verify local and federal compliance before purchase.