An essential part indeed, the 5 mm x 5 mm x 35 mm axle key is used on a number of Shoprider power chairs in the Streamer series. It was also used on the Pride Mobility Rally and Rally Shopper scooters, as well as the Jet 1 HD power chair.
The humble axle key may also be referred to as a shaft key, but whatever the nomenclature, this little part does a very big job. Without it your scooter wouldn't move.
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