These plug cutters are made to fit the Linbide counter bore drills. You will need a bench saw and a drill press to make the perfect plugs. HOW TO USE: 1 First trim the edge of the timber true and square, this will give you a clean face to cut the plugs out from. 2 Once you have done that, take the timber and place it with the trim and square edge facing up so you can cut the plugs out using a drill press. 3 Once you have drill all the plugs required out of the timber, place the timber back on the saw beach appropriately 15mm in deep from the stop on the bench saw. 4 Once you have sawn along you will end up with perfect plugs all the same size etc. 5 The plugs will fall out ready for you to place into the counter bore holes made by the matching Linbide counter bored drill.