BUY IN BULK AND SAVE: Great value in this 660' reel of Explosive Red tennis string, PREMIUM POLYESTER STRING FROM DUNLOP: Premium polyester material for predictable control and feel, OUTSTANDING DURABILITY: Heat treatment in the coating provides a smooth low friction surface for added durability, GREAT TENSION HOLD: Revolutionary process provides long lasting tension hold, ADDITIONAL PRODUCT DETAILS: GAUGE: 16/1. 30mm. LENGTH: 660ft