JOOLA Dynaryz CMD The Dynaryz CMD is made for professional players who like a medium-hard sponge. The strongly boosted sponge provides great touch and control combined with the power of the professional rubber. JOOLA Dynaryz CMD has a grippy surface, unlike the Joola Dynaryz ZGR which has a tacky top-sheet. The tacky top sheet would not work well with the medium-hard sponge.