WARNING: DUE TO THE NATURE OF THESE GALVANISED CASTINGS THE MEASUREMENTS GIVEN HERE CANNOT BE PRECISE. WE THEREFORE DO NOT RECOMMEND THAT ANY BOLT HOLES ARE PRE-DRILLED PRIOR TO INSTALLATION. A structural base plate for all aspects of vertical post support. This fitting when used as a base plate for guardrailing should always be positioned with the holes across the line of the guardrail to give maximum strength. The holes in the base plate are large enough to enable the use of mechanical or chemical anchor fixings.