Butterfly Tenergy 05 FX Table Tennis Rubber Soft， Highly Flexible Spring Sponge Class: Super Speed Speed 13 Spin 11.5 Density 32 Tenergy has proved to be an outstanding success， combining High Tension Technology with "Spring Sponge". Tenergy has risen to the top of the charts; now there is further development which maintains high performance levels with greater control. Tenergy 05-FX combines High Tension Technololy with a softer version of "Spring Sponge".