Yonex has introducesd the Polytour Spin G 125 16L tennis string. New SIF (Silicone oil infused filament) technology enhances string movement for great snapback. Pentagonal structure and new SIF Technology creates heavy, ball crushing spin. Composition: Pentagonal shaped monofilament core finished with high polymer polyester. Length: 39 ft. (12m) Gauge: 16L (1.25mm) Color: Red Yonex Tennis String PTGG125R