TIMCO Concrete Screws Flat Countersunk Yellow - 7.5 x 50

Designed to replace traditional masonry fixings TX30 TX Drive recess to reduce driver wear & prevent camming-out Serrated V-threads to achieve optimum insertion into all masonry types Zinc plated and yellow passivated for increased corrosion resistance High-Low thread on first 30mm to aid insertion and reduce torque Ideal for fitting windows and door frames Flat countersunk head with five locking ribs All steel, non-flammable fixing conforming to BS 7671 standard's 18th edition, which requires wiring systems to be supported by materials which are unlikely to prematurely collapse in the event of a fire., Weight: 1.763698096 Pounds, Manufacturer: TIMCO