Athearn RTR replacement motor with hex flywheels (for all models except  switchers, RS3's)     

This is replacement motor for older Athearn Blue Box or RTR locomotive motors, not Genesis. Flywheels are Hex drive not the old ball and finger style that came on earlier models. If your loco already has Hex drive couplings you should be able replace motor and reuse original couplings that came with the loco. Make sure you put couplings back  where they came out, one side might be a different length.

If your loco has old ball and finger couplings you need to use our #12034 Hex coupling combo set: