Smith & Wesson M&P AR Oops Kit. This kit is full of many AR springs, pins, plungers, and detents that are constructed of steel and are either unfinished or finished in black. This kit includes springs, pins, and detents for the bolt catch, buffer retainer, disconnector, hammer, trigger, pivot pin, takedown pin, selector, trigger guard, and the magazine catch. These parts are perfect to use for an emergency replacement stash and are great to have in the spare parts chest or included in an emergency field kit. This kit is proudly made in the USA.