This highly accurate Varmint Exterminator Barrel Kit offers a threaded muzzle on the barrel so that muzzle brakes or sound suppressors can be fitted. Precision machined from 416R Stainless Steel, the barrel features a Matched Carpenter 158 Steel Bolt which has been magnetic particle and high pressure tested. It is machined to mate with the barrel’s Compass Lake specification chamber for utmost accuracy. Button rifling is 1 turn in 8 inches – right hand twist for optimum accuracy with a wide range of heavier .223 / 5.56mm varmint bullets. The Kit includes all parts forward of the upper receiver for your custom rifle project: Picatinny Rail Gas Block; rifle length gas tube and pin, and Windham Weaponry’s 6061 machined aluminum Free-Float Forend with specialized barrel nut, rear knurled locking ring, sling swivel/bipod stud, and A2 Flashhider and Crush Washer. The vents on the Free Float Handguard are compatible with 3-slot and 5-slot M-Lok rails.The barrel is matte finished to cut glare, and is fluted to reduce weight, increase barrel surface and add rigidity.