The Stiga Factor is a 4-star professional racket with ITTF Approved Stiga S4 smooth rubber with 2.0mm sponge. Factor is the ultimate combination of two revolutionary technologies, ACS and TUBE, offering you increased speed, spin and control. The ACS Technology allows very high speed to be combined with maximum springiness/elasticity in an ultralight rubber with outstanding control. The Stiga TUBE bats are manufactured using a new technology where the middle veneer has gone through a revolutionary treatment. CLASS: OFF. Flared handle.