The SRM 1216 is a semiautomatic shotgun that uses a unique 16-round detachable magazine made of four individual 4-round magazine tubes that the operator rotates as needed, referred to as manual index. The 1216 offers ambidextrous controls as the charging handle, bolt release, safety controls, ejection port, and sling plate are all configurable to a left or right position. Top mounted picatinny rails allow for the attachment of sights and other accessories. An interchangeable bolt allows for the use of both lethal and less than lethal ammunition.