High Performance for a Topspin Attacking Strategy "Spring Sponge" is the latest innovation from BUTTERFLY. It is the sponge of the coming era. The well-known High Tension technology of BUTTERFLY is now combined with "Spring Sponge" to produce a new rubber family: TENERGY. TENERGY 05 is the first family member; the special feature being in the original shape of the pimples. The product carries our development code No. 05 and merges High Tension technology with the characteristics of a highly grippy rubber. TENERGY 05 has already been evaluated by a large number of leading players, as well as by scientific measurement, as the best rubber for spinning the ball, both when serving and during a rally. Do you look for a high quality rubber for your topspin and attack strategy? Then TENERGY 05 is the right answer Speed: 13,0 Spin: 11,5 Hard: 36° 1.7 / 1.9 / 2.1 mm