Easy to push: The smooth bearing can easily slide, then push the door without difficulty. The bottom of the floor guide is flat and does not damage the door and floor - Glides smoothly and quietly. Suitable for: The adjustable sliding door rollers are suitable for door width from 30mm to 84mm. Easy to install: No groove needed for the door, just attach two screws into the floor bar, then pull the roller guide stays in place. < p>Package contents: 1 guide, 2 screws, 1 hex wrench, 2 ribbed plastic anchors, all necessary hardware is included. Suitable for door covering with thickness from 30mm to 84mm Durable and premium material: sturdy carbon steel and nylon roller, black coating is wear-resistant and provides more long lifespan. Welcometomeet