This is an incredibly affordable doweling jig for woodworkers who want a quick joint without a lot of fussy layout. Many doweling jigs require that you make a mark on the inside edge of the joint, meaning you either have to transfer marks from the face to the edge, or measure and mark with a tape measure. Since this jig is transparent, layout is much simpler. Just set the two parts together and strike a line across the center of the joint. The see-through reference lines allows you to line up the jig perfectly. Clamp it in place, drill and you’re done