This kit is designed to work with the Momentum Carbon Fiber Motor Mount and MBS ATS.12 Trucks. Kit includes: 2pcs 62T #25 Sprockets Steel Black, 2pcs #25 Chain, 2pcs 12T #25 Motor Sprocket 8mm Steel Black,10pcs M4x70x60mm Bolts,10pcs .500" Nylon Spacers. Wheel sprockets are machined with MBS bolt pattern " not shown in picture".