Hardinge 5C Square Smooth Collet, 2mm Hole Size Collet for holding workpieces in a lathe or other machine tool Type 5C square smooth collet with a through-capacity of 45/64 or 19 mm Overall length of 3.281 and a back bearing diameter of 1.250 External right-hand 1.238 x 20 draw bar threads are heat treated for long life Hardened and ground spring steel for accuracy and resistance to wear and breakage