The Brownells Bore Scope Guide ensures that your bore is protected when using standard Hawkeye Precision Borescopes. The Bore Guide fits into all action with a standard body, such as Remington 700, Ruger, Winchester, and Sako. This Bore Guide prevents additional damage when inspecting bores for existing damage or wear. Will fit receivers with bolt diameter of .700". Mfg: Brownells SPECS: Delrin construction. Fits actions with standard interior dimensions such as Remington 700, Ruger, Winchester, and Sako.