MEROCA Bicycle Crankset Chainwheel 104BCD MTB Bike Crank Aluminum Alloy with Bottom 170mm Brand: MERCOA Length: 170mm Model: CX square hole crank Material: aluminum alloy BCD: 104mm Color: black/red Crank weight: about 510g Compatible: 8/9/10/11 speed Model: Snail round BCD 104 chain ring, 4-arm Tooth: Narrow and wide tooth Color: Black Red Thickness: 4mm