The child has to lift and press the handle of this spinning top to start it spinning. They become mesmorised as it blends into a rainbow of colour and emits a humming sound which changes in tone and volume, depending on the speed.
I would introduce this before your baby has the fine motor skills to use this, right just before they are about to crawl. It would make a great incentive as something to attempt to crawl towards.
A suction cup keeps this beautiful top stable while spinning.