vents in the body of the compensator 16 for redirecting gas fig1 3 the present invention thus provides an assembly of parts 10 for use with a shotgun in which the one shotgun may be used with multiple chokes and one compensator 16 and a single choke 12 may be used with a variety of compensators the locking nut 14 has internal threading 24 and a pair of corresponding wrench flats 28 on the outside surface of the locking nut the wrench flats 28 to assist the shooter in securing the locking nut 14 to the compensator and choke fig5 the compensator 16 includes two direction ports 30 to vent the gas and two expansion chambers 32 that provide for a gas expansion surface area two compensator exit ports 38 restrict the diameter of the compensator and two areas of tapered geometry 36 allow for a smooth transition to the restrictive diameter of the exit ports 38 the compensator 16 also included three flats 18 on a portion of its outside surface the flats 18 assist in lining up the direction ports relative to the shotgun barrel fig5 7 while the choke 12 and compensator 16 fulfill their respective particular objectives and requirements the assembly of the parts 10 departs from the conventional concepts and designs of the prior art and in so doing provides.