Designed for comfort and resilience, the unique Volkl V-Feel Black Silver Spiral 17 features a similar construction to the popular Power-Fiber II. A unique bonding process allows a larger percentage of the space to be fill by fibers instead of bonding resin, resulting in improved tension maintenance and consistent performance. Specialized metallic helix coils surround V-Feel for increased texture and improved spin generation. The larger outerwrap fibers help to increase durability without greatly sacrificing elasticity. Our testing staff enjoyed the soft feel as well as the added spin, but did notice a slightly stiffer feel and lower power from the typical multifilament string. Construction: Multifilament polyamide Gauge: 1.25 mm / 17g Color: Black / Silver Length: 40 ft / 12.2 m Need help selecting a string? Check out our Choosing The Right Tennis String Guide for more assistance.