Highlights For 110 through ¾ size instruments 110 through ½ size available in medium tension; ¾ size available in light, medium or heavy tension Ball end strings with yellow and blue silking Stranded steel core with nickel winding; 110 size A and D stainless steel and E tungsten-nickel winding Stranded steel core provides optimum playability and produces a clear, warm tone Description D'Addario Helicore Orchestral double bass strings are multi-stranded steel core strings that produce a warm tone quality with excellent bow response. The core design makes for strings that are very easy to play under the left hand. Damping is optimized for arco use, but they also work well for pizzicato applications where a very warm, less-sustaining sound is desired. All D'Addario strings are designed, engineered and manufactured in the USA to the most stringent quality controls in the industry.