THIS KENNAMETAL CAT40 COLLET CHUCK HOLDER IS A PIECE OF TOOLING WITH A CAT 40 TAPER TYPE. THE OVERALL LENGTH (OAL) OF THE ENTIRE PIECE IS 8-1/4 INCHES. THE PROJECTION IS 5-1/2 INCHES. THE NUT FEATURES AN OUTER DIAMETER OF 2.50 INCHES AND AN INNER DIAMETER OF 1.00 INCH.