Bearing 6201 for 4T scooter wheels (manufacturer TATA). It sits in the wheel hub and lets the wheel rotate freely, absorbing the load from weight and impacts.
Replace it if it hums and has play, if rotation has become uneven or jerking has appeared. Do not delay replacement: a destroyed bearing can damage the shaft and the housing. Replace the bearings on both sides of the wheel if wear is noticeable on one of them.
