The Griffin Armament EZ-LOK Universal Fixed Barrel Direct Thread to EZ-LOK Adapter affords the user the ability to convert the suppressor to a much faster and more secure mounting solution on fixed barrel pistols. This Direct Thread to EZ-LOK Universal Adapter allows you to convert 1/2x28 or 5/8x24 threaded suppressors to receive EZ-LOK barrel adapters. The Direct Thread to EZ-LOK Universal Adapter 1/2"x28 has a .310" diameter bore, .22 cal is the maximum caliber supported with this adapter. The Direct Thread to EZ-LOK Universal Adapter 5/8"x24 has a .350" diameter bore, .32 cal is the maximum caliber supported with this adapter. Features17-4 Stainless Steel H900 treatedQPQ Nitride finish for attractive, durable black finishWrench flats for easy installationInside taper locks direct thread adapter onto barrel adapter