Purdy 144400335 XL-Series Swan Wall Paint Brush, 3-1/2"Purdy's XL Series is the most versatile brush series, designed for use with all paints and stains. Provide ultimate performance and versatility. XL brushes are highly recommended for both interior and exterior painting projects with all paints. Each brush style has its own hand chiseled formulation for maximum paint lift and smooth "no drag" application. The stiffness retention of XL brushes makes them especially high performing for outside painting