Spornette 964-XL X-Large double stranded ball tip nylon for longer hair lengths. Spornette's Double Stranded Nylon Tipped Rounders are the 3 top selling rounders featuring Double Stranded permanent ball tipped, non-snarl, tangle-free bristles. Double Stranded Nylon Tipped Rounder #964-XL 2.5 inch diameter double stranded ball tip nylon for longer hair lengths.