Purdy 144080220 Nylox Dale Angle Trim Brush Only 100% solid, round, tapered (SRT) Tynex nylon by DuPont is used at Purdy. Carefully tipped and flagged by Purdy craftspeople, Nylox filament provides greater abrasion resistance for increased wearability while its famous Satin-Edge finish provides the excellent painting performance only found in such chiseled, handcrafted painting tools.