Backup Tactical Revolver Cylinder Thread Protector Silver 1/2x28 For 9mm & 22LR Pistol .75 in Diameter. The Cylinder Thread Protectors will protect your revolvers threads from damage that can occur during daily use or from damage that could be caused by improper maintenance. The cylinder thread protector is easy to install and protects the threads from damage that can occur daily use or from damage that could occur during improper maintenance. These protectors have been tested and are machined with a Lifetime Warranty. Backup Tactical thread protectors protect your firearms and are designed to save your butt from damage that could otherwise occur due to a lack of maintenance. Specifications for Backup Tactical Revolver Cylinder Thread Protector: Manufacturer: Backup Tactical Color: Silver Threads per Inch: 1/2x28 Fabric/Material: Aluminum Alloy Caliber: .22 Long Rifle 9mm Luger Package Contents: Backup Tactical Revolver Cylinder Thread Protector