Moon Shoes

I have a pair of kid's Moon Shoes for sale.

The maker says:

Turn your feet into mini trampolines with Moon Shoes, the anti-gravity device powered by kids. With Stay Active Moon Shoes, kids can jump with anti-gravity effects for high bouncing thrills. Run, jump, hopscotch, pretend to be an astronaut and Space Walk here on earth.

Trampoline Shoes for Kids
Moon Shoes have a self-centring shoe platform with a non-skid grip surface, so you can enjoy sure-footed bouncing adventures. The adjustable Velcro straps fit right over your shoes, adapting to shoe sizes up to an adult size 8 UK. Rubber bands adjust to create the perfect bounce for all weights.

Physical Development
Movement based play helps to engage all our senses and build healthy hearts. Physical sensory toys, just like Moon Shoes, can support the development of motor skills, balance and coordination.