Apico front sprockets are precision engineered from high grade steel. These are a cost effective option when compared to OEM sprockets and are compatible across a range of motocross, enduro and trials bikes. GAS GAS EC 200-300 97-20 XC 200-300 18-20 FSE 400-450 02-12 SM/EC 450-515 08-09 RIEJU MR200-300 21-24 SHERCO 250 SE-R 14-20 300 SE-R 14-20 450 SE-F 05-24 500 SE-F 19-24 510 SE-F 07-13 450 SE-F Factory 17-24 500 SE-F Factory 19-24