You can order your Mud Buddy with the optional Qs muffler. See your dealer for details. Maximum performance and improved flow path will generate more torque and power than ever before! If you really want to move larger boats and loads faster, then these mufflers are for you. BPS offers a full line of performance stainless exhaust for large and small block Vanguard, Kohler shallow water mud motors. Each offers increased exhaust flow and more power for your mud motor. For more info, go to www.backwaterperformance.com