Fitment: Coleman CT200U,CT200U-EX,BT200X,Baja MB165,Massimo MB200,Axis M200 mini bikes. Specification: The 420 chain 20 tooth sprocket is the larger one of the two sprockets in the Coleman's jackshaft assembly, with 20 teeth and ID 17mm [.66"] +OD 86mm [3.38"]. Package Include:1 x 420# drive chain sprocket 20T,1x Jackshaft Sprocket Key,1x Chian Master Link Note: Be sure to measure your chain or current sprocket before ordering. 420 chain has 1/2" pitch and 5/16" roller diameter. Color: Black; Material: Metal; Condition: All New. FITMENT: 420 chain 20 tooth sprocket Coleman CT200U Minibike Coleman CT200U Trail Minibike Coleman CT200U-EX Minibike Coleman BT200X Minibike Baja MB165 Mini Bike Massimo MB200 Mini Bike Axis M200 Please check the measurements or contact us before you buy.