Dunlop Black Widow 16G Tennis String The Dunlop Black Widow 16G Tennis Strings have been designed for spin & durability, with a premium, high tensile mono-filament polyester construction in a hexagonal outer profile. > Tennis String > Construction: High-tensile, mono filament premium polyester > Gauge: 16 / 1.28mm > Profile: Hexagonal outer profile > Length: 12m Black 16G