The CBSDQ screw is suitable for fixing fibre cement board/timber to steel . It has a countersunk ribbed flat head, fine thread and drill point with wings. The wings ream a hole larger in the cement board/timber and break off when they hit the steel. This allows the cement board/timber to be pulled tight to the steel. Suitable for steel up to 3mm thick. Common Applications Fibre cement board to steel Cement board to steel Timber to steel I have 3 boxes of these u opened & untouched they was bought By myself for a job these 3 boxes was never used & we no longer using fixings .
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