Otter Creek Labs OTB Muzzle Brake Features The Otter Creek Labs OTB Muzzle Brake functions as a one piece adapter that mounts an OPS 12th model OCM5 or AEM5 suppressor directly to any 5/8x24 threaded barrel eliminating the need for custom collars or barrel modification. Machined from H900 heat treated 17-4 stainless steel the brake is built to handle repeated mounting and dismounting while standing up to the heat and pressure of muzzle blast. The included shim kit is the only approved method for timing the brake ensuring it is indexed correctly on the barrel every time it is installed. Shooters should never use a crush washer with this device as doing so voids the warranty. This raw heat treat finish gives the OTB Muzzle Brake a distinct unfinished steel look while retaining the same strength as the black nitride coated version. Because the brake includes the timing shim kit in the box it costs more than the standard OTB fast attach but removes any guesswork from achieving correct orientation. Compatible with barrels up to 0.75 inches in outside diameter with at least 2.05 inches of exposed barrel from the shoulder this brake works on a wide range of rifle configurations. For shooters running an Otter Creek Labs quick attach suppressor system the OTB Muzzle Brake offers a reliable repeatable mounting solution. Otter Creek Labs OTB Muzzle Brake Specifications Manufacturer: Otter Creek Labs Model: OTB Muzzle Brake Color: Natural Material: Steel Thread Pattern: 5/8x24 Available At: GrabAGun