A device to bind the edge of a hat brim that is easily applied to a hat and can be reformed and removed as desired. A malleable forming member, enveloped by a covering material, allows the device to be folded over the edge of a hat brim and the brim formed to the desired curvature. The covering material that envelops the forming member provides a finished appearance to the device and may be comprised of textiles in any color or texture, so it may be interchanged with other devices to suit the appearance of the hat or its wearer.