Happy and unhappy balls
PIRA: Unknown
The unhappy ball is made of a rubber called Norbomene polymer, which possesses excellent impact absorption properties. The happy ball is made of common neoprene. Although both balls are identical in shape, the unhappy ball has a small repulsive modulus of almost zero, while the happy ball rebounds very well under standard 10 - 30 degree C conditions.
Equipment | Storage |
---|---|
happy and unhappy balls | 021-7B |