ROTOMORS 31" 3-JAW BIG BORE CHUCK Automatic Self-Centering Chuck with Big Thru Bore and Built-in Hydraulic Cylinder Model MC-ID, Stock# K15852 DESCRIPTION: This type of self-centering chuck with hydraulic power is suitable for heavy production lathes. The feeding oil comes through holes drilled in the back mounting surface of the chuck. This allows you to fully use your machine's spindle bore. CATALOGUE SPECIFICATIONS: Chuck Diameter............................................ 780mm ( 30.70" ) Chuck Thru Hole........................................... 385mm ( 15.15" ) Jaw Stroke................................................ 20mm ( .78" ) Clamp Force at 30 Bar PSI................................. 55,000 LBS Max RPM................................................... 800 RPM Approximate Chuck Weight.................................. 1,700 LBS CONDITION: Appears to be in Very Good Condition !