Rawlplug UNO Plugs are truly universal plugs which fix into any wall, ceiling or floor. Suitable for use in concrete, brickwork, stone, blockwork, plasterboard. They have a unique design with expansion throughout the length of the plug. They expand at the top giving instant grip. Anti-rotation features prevent spinning in the hole. Screw Head Size Yellow 3-4.5mm Red 3.5-5mm Brown 4-6mm Blue 4.5-6mm Grey 5-8mm Typical Applications - Shelving and cabinets - Suspended ceilings - Switch boxes - Trunking and cable trays - Water heaters and radiators These Rawlplug UNO Plugs have the following specification Colour Brown Size 7 x 30mm Pack Size 900 (450 x Plugs, 450 x Screws) Supplied in a jar with 450 Brown UNO Plugs and 450 matching screws.