This is a spring, detent and pin small parts kit meant for AR-15's, but most of these parts are also interchangeable with AR-10's. Compatibility with the M&P 15-22 will depend on how many of the parts are interchangeable with standard mil-spec parts as that is not something Smith and Wesson lists. It is not an ambidextrous kit as there are no parts that affect any ambidextrous controls, like the safety selector.