This Evo version comes with a slightly harder rubber formula than the famous frictionless Anti-Spin rubber A-B-S 2. This shortens the contact time during the ball impact and enables A-B-S 2 Evo to produce a bit more spin reversal.1.8mm (best spin reversal, low speed) 2.1mm (best spin reversal, low speed) 2.3mm (very good spin reversal, even lower speed, very good control) 2.5mm (still very good spin reversal, slowest version, very good control)