Liberty Precision Machine Thread Protector Nitride Black. 9-24 muzzle devices while a silencer is not in use. Compatible with all LPM Rearden MFG and Q LLC muzzle devices. 17-4 H900 Stainless Steel Black Nitride finish .25 Ounces 15/16 and 7/8 Hex features for secure mounting Specifications for Liberty Precision Machine Thread Protector: Manufacturer: Liberty Precision Machine Color: Black Fabric/Material: 17-4 Stainless Steel Stainless Steel Quantity: Single Pack Finish: Nitride Weight: 0.25 oz Package Contents: Liberty Precision Machine Thread Protector Liberty Precision Machine LPM-2020: Thread Protector Nitride Black