THIS ITEM IS A SET OF FOUR COMMAND CAT-40 ER-20 COLLET CHUCKS, MODEL CAT 40, DESIGNED FOR MILL TOOLING. MANUFACTURED FROM STEEL, THESE CHUCKS FEATURE A CAT40 SPINDLE TYPE AND INCLUDE COOLANT THROUGH CAPABILITY. EACH CHUCK HAS A 4-INCH PROJECTION LENGTH. THE TOTAL SET WEIGHT IS 4.00 LBS.