Address : Using a speedball for the first time can sometimes be a difficult task to master but once accomplished it has already improved and taught you a variety of boxing skills such as Hand eye co-ordination and rhythm along with building up that upper arm shoulder strength and fitness for improved power and performance. For a speedball to be effective it needs to be cylindrical and inflated to the correct pressure and will require regular on going inflation checks to maintain performance. The outer shell is made from a durable cross fibre synthetic material that incorporates a sewn in rubber inflatable bladder with a butile valve to minimise air loss. The hanging loop is also an important feature as this needs to be durable but not so thick and wide that it causes unnecessary friction that will wear the loop and slow down the pace of the ball in motion. Inflation P.S.I – Maximum 4lbs pressure Do not over inflate.