Northfield Precision Instrument Corporation introduces their Model 450WHF chuck. It uses a special 4-port air tube (and special piston) to allow for open / close / autolube / air-detect functions. The top plate (with pin) is a radial banking surface (side of pin only) which picks up the side of the customer’s part when it is loaded (and twisted into position) into the chuck. The three small pads with tiny holes in the very center of the chuck are used to rest the part against (tops of pads) whilethe holes are used for the air-detect function (positive indication that the part is indeed loaded into the chuck).