This Genuine Ruger Factory Accessory is compatible with Ruger LCP II pistols chambered in 22 LR. The threaded barrel accepts any 1/2-28 (Class 2A) muzzle device. This kit contains a factory-manufactured stainless-steel barrel for optimal fit and function. Barrel changing is quick and easy with no gunsmithing required. Barrel cap adapter red recoil spring and 7/16 wrench included. Made in the USA.