104bcd conversion base adopts CNC cutting of aluminum alloy to the accuracy of product use The 104bcd conversion base is perfectly compatible with the electric bicycle medium mission engine, v / 36V / 48V 250W 350W 450W 500W 750W motor 104bcd the conversion base material is aluminum alloy material, the hardness is much higher than the original, strong and steel chain wheel. The 104bcd conversion base can be used with many mountain bike accessories and can be combined with a variety of configuration options, suitable for XC AM multiple , city trip Category: Cogwheel Plate tooth: 34-42T Use: Mountain bikes Use: Road bikes Use: Children's bicycles Use: For BMX Model Number: crankset for mid motor kit 104BCD: 4 Chain Ring Bolts 104BCD Weight: 40g colour:black Material:Aluminum Alloy size:about 170mm Package Contents: 1 * adapter plate 4 * M5*16 screws Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.