A long time leader in synthetic gut performance and technology, Wilson has reintroduced natural gut strings to their line up. This high quality natural gut uses only top quality beef serosa to produce a consistent and responsive string. If you are looking to get the ultimate from your racquet, then natural gut string is the way to go. By far the most popular choice since the pro tour started, natural gut is powerful, offers great feel and is the number one recommended string for arm safety. In 17 gauge form, Wilson Natural Gut offers optimum playability with slightly less durability compared to the 15L and 16 gauge versions of this string. Gauge: 17 / 125 mm. Construction: Premium quality natural gut. Length: 40 feet / 12 m. Color: Natural.