Fits Raptor 660r ALL YEARS 01-05  True duals= "one equal length header on the right and one equal length header on the left" THE 660  5 VALVE HEAD LOVES TRUE DUAL MONSTER EXHAUST ONE TWIST OF THE THROTTLE AND YOU WILL UNDERSTAND!!!!!!  Also if want to run the beloved FCR carburetors they will fit!!! ATV Exhaust Systems Yamaha Raptor 660 Dual exhaust System Black Powder Coated 15"  Cans with Polished Caps/Tips fits all years *  Why our system eats the competition: ! * Exclusive design ( patent pending ) * CNC Billet pinch design (eliminates hose clamp! ) * 4 screws to remove guts for repacking (eliminates rivets) * Cool 12 way directional tip adjustment * Over 25 years of Research & Development in 4-stroke Pipe Design * Black Powder Coated Aluminum Exhaust Canister Huge Flow Thru design * MonsterPipe™ STAINLESS STEEL HEAD PIPES AND FULLY STEPPED MID PIPE means Monster Horsepower & Torque Increase ! * MonsterQuad logo is  Lazer stainless NOT a sticker ! * Weight savings over stock. * Dyno Proven We carry exhaust systems for all the following Performance ATV's. YFZ450, TRX450r, Raptor 660, Raptor 700, Rhino 660, LTZ400, KFX400, DVX400, KFX700 V-Force, Polaris RZR, Yamaha Rhino 660 & 700 Worldwide shipping available use " ask seller a question " feature for shipping price & availability Please include shipping address.