4mm coupling for Robot Smart Car Wheel

The 4mm coupling for robot smart car wheels is a shaft coupling sized for 4 mm motor shafts that connects the motor to the wheel. It lets you mount robot car wheels on small DC gear motors whose shaft does not fit the wheel directly, and it passes the motor's torque to the wheel through a firm connection. It is useful when building or repairing 2WD and 4WD robot cars, rovers and other wheeled robots.

4mm coupling Specifications

• Shaft size: 4 mm
• Type: motor-shaft-to-wheel coupling (hub adapter)
• Use: mounting robot smart car wheels on DC gear motors with 4 mm shafts
• Quantity: 1 coupling

4mm coupling Applications

• Robot cars and rovers built with small DC gear motors
• Fitting different wheels to a robot chassis
• Replacing a worn or lost wheel coupling
• Robotics competitions, school clubs and STEM projects

What's in the Box

• 1 × 4 mm coupling for robot smart car wheels

Tip: Measure your motor shaft with calipers before ordering and check its shape (round or D-cut); for 6 mm shafts, choose the 6 mm coupling instead. If the coupling uses set screws, tighten them against the flat side of a D-shaft so the wheel cannot slip, and use one coupling per driven wheel.

Orders placed before 14:00 are ready for pickup the same day. Delivery across Lebanon usually takes 1–3 working days.