C521 Pro Flat Contour by Crown Brush. 

Thanks to its densely packed fibers and flat, compact head, the Pro Flat Contour brush easily glides under the cheekbone and with the hollow of the cheek, creating a very dramatic and linear Contour application. The soft bristles blend and disperse the product without losing their compact shape, leaving you in total control over product application. The Pro Flat Contour Brush is also the perfect tool for baking and cleaning up Contour lines due to its flat surFace and its ability to pick up large amounts of loose setting powders.

Bristle Profile: High Grade synthetic fibers, Incredibly durable, Indefinite lifespan with proper care, Can be used with liquid, powder, and cream cosmetics.