The Robert Sorby STB200 Original Stebcentre 7/8" x #2MT is a revolutionary spur drive center that replaces traditional spur drives and gives all the great Stebcentre advantages. It combines a spring loaded center point with a ring of razor sharp teeth. By winding in the tail stock the degree of "bite" can be varied while still keeping the center point firmly located. This offers many advantages. With a light setting this offers safety for the novice turner because the work piece simply stops revolving should a dig-in occur, rather than causing kick back. In time critical production turning, the teeth can be backed off with the point still in place, so the work piece can be stopped and checked without removing it from the lathe, and finished pieces and blanks can be exchanged by backing off the tail stock, rather than starting and stopping the lathe. Size refers to drive face diameter. Comes in diameters of 1/2", 7/8", and 1-1/4". Robert Sorby. England