This attachment offers a simple and convenient way of converting a pillar drill into a lightweight morticing machine, provided that the collar diameter (the part where the chuck guard normally fits) is either 65mm, 60mm or 55mm. Best mounted on to an MDF base plate (not supplied), the attachment works well once the mortice bits have been cut down to a length to suit the pillar drill being used. When installing the chisel and bit together, ensure that there is a minimum of 1.5mm of clearance between the bit and the chisel and that the bit is securely tightened to avoid damage to the chisel. The attachment has a 65mm mounting diameter and is supplied with an adaptor which allows for fitting to 60 or 55mm diameter collars. Takes 3/4" shank chisel and bits (not included).