No additional plugs required, making the WHO screw a user-friendly and time-efficient fixing solution. Countersunk Head Made of hardened steel, electro-zinc coated. Imposes less stress on substrate during installation due to no expansion force. Small hole diameter giving high loads. Easily removed for temporary works. Suitable for use in pre-drilled 6mm diameter concrete, full and hollow bricks, stone and structural clay tile and without pre-drilling in aerated concrete and timber. Applications include use with door and window frames, suspended ceilings and lightweight steel angles. Steel construction. Expansion-free, imposing less stress on the substrate during installation. High load resistance from a small hole diameter. Easily removed for temporary works. Ideal for all types of window and door frames and stud partitioning. Non-expanding self-cutting fixing for use in dense concrete 30Nm or aerated concrete and timber. The Rawlplug concrete screws have a high load resistance and are also extremely easy to remove, allowing them to be used as a temporary fixing measure.