This is the part of the spindle that will hold and grip the end mill at the spinning part of the spindle. This is a collet for smaller spindles with the ER-11 specification. This collet will accept tools with a 1/8" (3.175 mm) shank. This collet has a high precision TIR (Total Indicated Runout) of 0.0002". The bore measures 1/8" .125 inch (3.175 mm) to hold end mills that have a 1/8" shank. The shank of an end mill is the smooth part of the end mill that is inserted into the collet of the end mill. General dimensions for ER-11 collets: D (Outside Diameter): 0.453 inches (11.5062 mm) L (Overall Length): 0.709 inches (18.0086 mm) L1 (Front Tapered Length): 0.531 inches (13.4874 mm) L2 (Rear Tapered Length): 0.098 inches (2.4892 mm) This Collet Bore Diameter (d): .125 inches (3.175 mm)
