Description: Brand new. Made from high quality aluminum, durability and corrosion resistance. Fits Frameless Shower Doors: the package includes 4 pieces of M 6054 frameless shower door top bracket roller assembly, the inside diameter of the bracket channel is 1/4 inch wide; Only suitable for sliding shower doors with drilled holes in the glass panel. There is a 3/4" ball bearing roller that is mounted on aluminum brackets, making sure the door is level after installing the brackets; And, the M 6054 bracket channel has an inner diameter of 1/4 inch wide. Easy Installation.Adjustable by sliding the roller up and down in the diagonal mounting slot, then tighten; Please note: it is only suitable for sliding shower doors with drilled holes in the glass panel.