[Mute and prevent scratches] The height of the fixed feet of office chair glides is close to the height of the mounting feet. It is suitable for preventing the air pressure rod from damaging the floor. [Suitable for all kinds of floors] Fixed stationary castors have good traction, maintain stability on smooth floor surfaces (wood, tiles, laminates), provide greater traction than casters, and reduce friction, vibration and noise. [Excellent caster replacement] Replacement glides are suitable for different swivel chairs (executive chairs, office chairs, game chairs, tables and chairs) very suitable to roll the stool or office chair into a more stable fixed type. [Efficient installation] Replacement office chair wheels are easy to install and remove, no screws are required, just grab the old casters and pull them out. Then push chair wheels replacement into the holes. Good traction for smooth movements: These sliding devices maintain stability on smooth floor surfaces (such as wood, tiles, and laminates) while providing greater traction than casters. Easy to install: Very easy to install without any tools. Than casters: By avoiding the "rolling chair effect" when getting up from a table or desk, a stable seat is provided for people who have difficulty moving in and out of the chair. Protect your carpet: Will not damage carpet like some casters. Perfect for atypical situations: Suitable for use on moving surfaces, such as boats and RVs, and on floors that are not perfectly flat. Heavy-Duty & Super Quiet Fixed casters have good traction, maintain stability on smooth floor surfaces, and provide greater traction than casters. Includes 5 foot pads to help reduce friction, vibration and noise. Color: Black Material: Nylon Size: Base diameter 52mm, plunger: 11x22mm, installation height 35mm Package Contents: 5 x Swivel chair fixed casters 5 x Foam pads Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture to be slightly different from the real thing. The measurement allowed error is +/- 1-3cm.