Babolat strings are known for their higher quality construction and top end materials. The Babolat SG SpiralTek Tennis String is a control Syn Gut that’ll help you get the extra control and durability you need with hybrid stringing. Use the SG SpiralTek on the crosses to bring back the comfort that a full poly string bed lacks and enjoy the best of both worlds. Spin and Control. Polyeamide single wrap made for comfort and durability.