Glock Factory Barrel Thread Protector with 1/2"-28 Thread for Glock 17 Gen5, Glock 19 Gen5, and Glock 34 Gen5 with a black diamond like carbon coated finish. This thread protector is a factory original from Glock. Factory replacement parts are manufactured to the exact same specifications and tolerances and use the same manufacturing materials as the original parts which guarantees excellent fit and reliable operation.