These Remington stainless bolt stops are needed for any rifle that is going to be out in wet weather. This trigger part area is tough to keep clean or dry. Adding some stainless parts keeps the rifle working in adverse weather conditions. A perfect upgrade to any M700 or M40 rifle. This part is used on all XM-3 rifle builds and with all stainless receiver rifles. This replacement part is a factory original from Remington. Factory replacement parts are manufactured to the exact same specifications and tolerances and use the same manufacturing materials as the original parts which guarantees excellent fit and reliable operation.