Plasplugs Originals™ General-Purpose Fixings are regular-duty, suitable for concrete, brick, breeze block and stone. The plugs feature multi-action grips, expanding barrels, barbed jaws and anti-rotate ribs. Typical applications: shelving, curtain poles, lighting, hooks and brackets, pictures and mirrors. Colour: Red.Screw Type: No.6-12 (3.5-5.5mm).Drill Bit: 6mm.