4-SPEED CRANK AXLE GEARBOX. This 4-Speed Crank Axle Gear Box is small but has a lot of power. There are four gear ratios to choose from, including the slowest ratio that allows for two rotations per minute.
This 4-Speed Crank Axle Gear Box is small but has a lot of power. There are four gear ratios to choose from, including the slowest ratio that allows for two rotations per minute. Two crank arms are included for added flexibility in the design of projects.
