Why are my plugs not flush with the surface once inserted?

Kreg pocket-hole plugs are designed to work with wood from 3/4"- to 11/2"-thick. Because of this, it is possible that once the plug is inserted into your pocket hole, it will protrude past the workpiece surface. To eliminate any excess material and bring your plug to flush, we recommend using a flush-trimming saw or a flush-cut laminate bit in your router to trim off the majority of waste, and then sanding to flush.