Sumnacon Stainless Steel Shower Glass Door Knobs, Modern Elegant Bathroom Round Back-to-Back Shower Door Handle Pull for 0.16" to 0.63" Doors, Exterior Interior Door Handle Knob (Clear) It had two clean plastic washers. The plastic washer is a great idea, especially for dual sliding glass doors to keep the metal handles from chipping the glass edge of the other door where they impact each other as either door is opened. Very nice, solid and heavy knob. Use this knob on a sliding glass shower door.The knob matched really well with the other fixtures in the bathroom.Fits 4.0mm(0.16") to 16.0mm(0.63") Thick Glass and 8mm(0.31") diameter hole; Mountable to many types of doors including glass, fiberglass, metal, and more; can be installed on interior and exterior front doors, shower doors, gates, wine cellars, sliding barn doors & more. Double sided cylinderical knob, easy installation ,convenient to grip. Solid stainless steel construction, long lifespan and will not rust. Perfect addition to any kitchen or bathroom door. This shower door Knob adds a simple elegance to a frameless shower enclosure. The sleek, cylindrical shape is functional without detracting from the beauty of all glass door.