Standard Duty Rotating Centre suitable for general purpose use.
Available as a MT1 or MT2 fitting.
Rotating Centre has a 60 degree point with twin deep groove ball races.
It is fairly easy to identify which MT size you need by simply measuring the hole diameter in your tail stock.
MT1 = 12mm MT2 = 18mm MT3 = 24mm (MT1 & MT2 being the most popular).