Yonex Polytour REV 125 - OrangeYonex Polytour REV 125 Orange As a co polyester monofilament, Yonex PolyTour REV will give you the needed control to execute your most powerful hits. Packed with 8 sides, PolyTour REV not only puts a tight grip on the ball, it also features SIF technology (Silicone Oil Infusion), which helps the strings snapback powerfully during impact for extra ball rotation. This co polyester also has above average comfort for a poly based string, making it an