For deep hole saws, a guide stick is required . The entire 160 mm cutting depth. Long carbide hole saw with 10 or 12 mm adapter From 160 mm hole saw, the adapter attachment is 12 mm. The new guide stick can have both 10 mm attachment and 12 mm attachment so the guide stick works for all hole saws. NOTE The guide hole should ALLTIS be 10 mm with the new guide stick. Recommended for deep constructions Preparation for cavity insulation, double walls where two walls are cut with cavities and the holes must be opposite each other Drilling through Leca blocks for ventilation NOTE All hole saws have an adapter, so you only need to buy a guide stick to complete your hole saw. You must use a guide stick that is ordered separately. To make room for the guide stick, you must pre-drill a so-called guide hole. If you don't have a drill for this, you can buy this accessory separately.