Herewith Kizuna Duratech D61 Quality badminton stringing critique; Kizuna Duratech D61 high quality badminton string by ERR badminton restring Singapore. Kizuna D61 is simply introduced in 2019. This Kizuna D61 badminton string as you may begin to see the gauge is skinny only 0.61mm, but this string capable to supply “tough†sensation.