A bronzer brush is a brush specially designed to apply powders and foundation to the face. It must have long, soft bristles to be able to apply the loose powder in even concentric strokes on the face. You do not want the powder to look like it has been put on in layers or on separate spots on the face. You want it to blend the powder in an even coat and that it will look natural like it is apart of the skin. You also want the brush to be able to apply the powder so it matches the natural skin tone. One thing is for sure you do not want a brush that will not bend with the contours of your face.