1.2.Made of metal material, high strength polishing, electroplating, no rust, no fading.3.Find the position where you want to install on the board and drill a hole , then pass through the screw from the back of board and thread tight to the knob.4.The spiral cabinet knob has a solid, durable construction providing long lasting hardware with an elegant, classy look.5.perfect for cabinet, dresser, drawers, cupboards, wardrobes in your home, bathroom, living-room, dorm and office.Diameter:30mmMaterial:Zinc alloycolour:colorPackage Contents:10 * Hardware handleOnly the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.