Forgefix concrete frame screw torx high low thread zyp forgefix cfs52 these forgefix high low thread concrete frame screws are zinc yellow passivated for increased resistance to corrosion they offer a virtually stress free fixing allowing close to edge applications they are through fixing eliminating the need for marking and re positioning when fixing batons etc the torx head of the screw enables increased torque control supplied complete with cover caps and torx bit extremely popular