Introducing Yonex BG Aerosonic Badminton String shreds the air with an exhilarating and powerful sound with the world's thinnest string. For players seeking high repulsion and a hard-hitting sound. Firstly, the Yonex BG Aerosonic Badminton String is thinnest badminton string in the world, which is only 0.61mm gauge. In addition, the Yonex features a "Compact Filled" construction, which means the construction of this string fills up all the gaps. Technologies within the Yonex BG Aerosonic Badminton String. The high-intensity nylon core gives greater durability than normal nylon. While a high-polymer nylon outer provides sharp feeling and high repulsion - exceptional all-around performance from an extra-fine string. Highly packed resin between the core and outer string removes gaps between core and string. Resulting in an ultra-fine gauge and incredible strength.