The Pro Jump M Series/F Series Rubber Soles features the following specifications… Suitable For – The Adult/Junior Rubber Soles are designed to fit the M-Series and F-Series Jumping Stilts as a replacement part Compatible With – These rubber soles MAY also be compatible with other brands of Powerbocks (however we can not guarantee this ) including PoweriZer PowerStrider Fly Jumper Jolly Jumper Air Trekker Air Runner Speed Jumper PowerStrider 7 League Boots PowerSkip and PoweriSer. If you are unsure after checking the photos and description the Pro-Jump Forum (search Google) may be able to advise if you post photos of your Jumping Stilts. Quantity Supplied – Two rubber soles are supplied What You Need To Fit – 4 bolts (not supplied) are needed to fit each sole to each hoof frame (i.e. 8 bolts in total)