EXHAUST STUD & INTAKE STUD KIT 50cc QMB139 & 150cc GY6 SCOOTERS THIS IS A REPLACEMENT EXHAUST STUD BOLT AND INTAKE MANIFOLD RETAINING STUD BOLTS IS FOR THE 4-STROKE, GY6 50cc & 150cc ENGINE. THESE DIRECTLY REPLACE THE STOCK BOLTS AND IT IS USED ON A WIDE VARIETY OF SCOOTERS AND ATV BRANDS AND MODELS THAT HAVE CHINESE BUILT 150cc GY6 & 50cc 139QMB ENGINES.* M6 x 1.0 x 31 mm* M6 x 1.0 x 63 mmFITS BRANDS LIKE TAOTAO, ICE BEAR, JONWAY, JMSTAR, TANK, ROKETA, SUNL, GATOR,AND MANY OTHERS