Hi Ben,
Poweriser and Pro-Jump are totally seperate companies, they may get the products from the same factory but both have there own independant trademarks registered.
The confusion occurs because people are reffering to these items as 1 product pro-jump & poweriser at the same time.
Pro-Jump and Poweriser are the only legal ones available in the country, so do not be tempted by the cheap quality copies that are available.
Thanks
Ian