All working parts precision ground and hardened Completely sealed for maintenance free operation! Turning: The unequaled rigidity of this toolpost and holders insure smoother turning without chatter or vibration! Drilling: Set enables you to drill by power feed with your carriage, instead of hand operation or tailstock 1/2" shank Can hold upto 5/8" boring bar the tool can be used on straight shank, for example :boing bar, u drill, twist drill, center drill and extension rod