Kit includes front and rear sprocket with same gear ratios as stock and a Gold Renthal R1-428 chain. Saves over 2 lbs. over the stock 520 O-ring chain and steel rear sprocket. Improves acceleration and responsiveness with less revolving un-sprung weight. Front sprocket is made from super strong nickel chromoly and is grooved to clear mud and increase chain life. Rear sprocket is made from 7075 T-6 aluminum which is precision machined with self-cleaning mud grooves and lightening holes. This item fits the following vehicle applications: compatible with Honda CRF230F 2003-2009.