Made of High Quality Tool Steel , this is a high quality product for your lathe machine * Used for threading and tapping purpose on the lathe machine * Die Holder Sizes 13/16", 1" & 1-1/2" . Tapping Capacity of the Tap Wrench : 1/16" to 1/4" & 1/4" to 1/2" * Die Holder Sizes 13/16", 1" & 1-1/2" . Tapping Capacity of the Tap Wrench : 1/16" to 1/4" & 1/4" to 1/2" * Comes in MT3 Shank, that goes inisde your lathe tailstock & intended job for threading / tapping is hold in rotating chuck. * The Die for threading purpose is hold in the various Die holder sizes. The internal bore threading/ tapping is done by mounting the tap wrench head as per tap size between the above advised range is moved toward the rotating job in the lathe's chuck.