Purdy 144380325 XL Series Sprig Flat Trim Paint Brush, 2-1/2 inch The stiffness of the brushes makes them ideal for outdoor projects with different temperatures and humidity A blend of Satin-Edge nylon (Tynex) and Orel polyester Each xl Brush has a unique hand-chiseled formulation for maximum paint lift and smooth "no drag" application Highly recommended for both interior and exterior painting projects The stiffness retention makes them especially high-performing for outside painting under hot and humid climate conditions Only solid, round, tapered Nylox (dyed nylon) and polyester filaments are used and our special tipping and flagging process brings our synthetic filaments as close to naturally flagged bristle as possible Hand-chiseled formulation for maximum paint lift and smooth "no-drag" application For varnish and enamel work