1. New gear design to reduce noise.
2. RC 550 electric motor, use 8.4V battery pack, super torque can start to .39 size engine.
3. Molybdenum (MO) produced by Power Metallurgy to increase the mechanical strength of gear box.
4. Including the positive and negative switch device that has the reversible function.
5. 8.4V power source (Battery) can start to .39 size engines of car or helicopter, mount an extra adapter can start aircraft engine as well.
1250 E-Starter Shaft W / Rubber Ring For Plane (not includ)