This little blender brush is a favorite for adding highlight to the inner eyes or just under the eye. The blender style also works amazing for blending out colour on the outer edges of your eye to create a detailed look or a smokey eye.
Mini Detail + Blender Brush - Innomineral Cosmetics
This medium-sized eyeshadow brush allows for easy highlighter application below the brow. It also has the ability to blend colors beautifully over the whole lid.