The forgefix hex head stitching screws are designed specifically for joining cladding sheets together they have a hex head and a self drilling point which enables speedy insertion the rubber washer beneath the aluminium flange expands under pressure to form a permanent weather seal the screws are zinc plated and have an elementech coating for superior corrosion resistance which is spray tested to 1000 hours they can join up to 3 sheets of 07mm thickness specifications size 63 x 22mm pack quantit