Double flanged with pre-drilled mounting holes.

The base comes in two sections which simply slot together and the top is fixed by putting the four screws provided into pre-drilled holes.

The purlins are attached to the ribs using a "hook" bolt, which hooks through a pre-drilled hole in the rib and is secured into the purlin.

The inlays were attached to what have been identified as chairs and footstools by copper alloy rivets, through pre-drilled holes.

With the drainage sill in place, drill down through the pre-drilled holes into the frame below.

Direct transmission: The retractable rod is lowered into the mat through a pre-drilled hole.

The first is that the blade can be removed and placed in situ through a pre-drilled starting hole.