Specifications Hign-concerned Chemical:None Special Features:Chain Sprocket Kit Item Diameter:7.6cm Item Weight:1.5kg Item Height:1inch Item Width:1inch Item Length:1inch External Testing Certification:iso9001 Model Name:420 Chain Sprocket Kit Name:LeSiRacing Item Type:Sprockets Material:Metal Origin:Mainland China 420 Chain Sprocket Kit Rear Sprocket 420 35T 145mm Front 420 13T 57mm 120L Chain for 50cc to 125cc Dirt Mini Bikes ATV Go Kart Feature: 1. Wide Application: The 420 chain front rear sprocket kit is specially designed to fit 50cc to 125cc dirt bikes, mini bikes, ATVs and 4 wheel go karts. 2. Sprocket Size: This Front sprocket drive gear is 13T. Center mounting holes are 1.18in apart and are compatible with 17mm engine countershafts. 3. Heat Treatment: To make the sprocket stronger, the sprockets are heat treated, which increases the strength of the sprocket, making it resistant to wear and tear very well. 4. Gear Curve Design: The sprockets also have an upgraded gear curve that helps reduce transmission friction, which helps extend the life of the chain. 5. Ideal Replacement: This kit is designed to replace the old one in different power sport vehicles using 420 chain sizes. The front/Rear sprocket is supplied with mounting screws. Specification: Item Type: 420 Chain Sprocket Kit Material: Steel + Steel Alloy Rear Sprocket: 420 35T 145mm Front Sprocket: 420 13T 17mm Application: Complete chain and sprocket set designed to replace old damaged chain and sprocket sets from originals to get your riding going again. Fitment: Fit for 50, 70, 90, 110, 125cc Dirt Pit Bike and Mini Bikes, ATVs, Go Kart Replacement for Coolster Replacement for Apollo Replacement for SSR and more Package List: This is a multi option link, and we will ship according to the buyer's choice. Please pay attention to your options before purchasing. Thank you for your understanding! 1 x 420 Chain 1 x 145mm 35T Front Sprocket 1 x 420 13T Rear Sprocket 1 x Fixing Plate 1 pack Screw Note: To avoid receiving the wrong product, please take the time to check and confirm the correct shaft, chain size and number of teeth before placing an order