Features:
1)  Great exercise that's fun for the entire family. 
2)  Improve coorination and flexbility.
3)  Burn calories and vent stress.
4)  Rocks back and forth with every punch.
5)  Providing the knock-dowm / instant-up motion that buildsendurance and sharpens reflexes. Even for practising martialarts.
6)  Extremely durable,rugged PVC construction.

How to use:
1. Pour some water or sand into the bottom hole.
2. Press the air pump by hand or foot to inflate.