★ECCENTRIC DESIGN: The inside of the ER32 collet nut is intentionally designed like off-centering to help mount the ER32 collet much easier.
This collet size is true imperial fractional size, not a metric converting size and the surface on this collet has been specially treated to increase its tool life.
★ACCURATE DOUBLE ANGLE for Improved Precision, with runout measuring 0.0003" for diameters of 1/8" and above, and 0.00059" for diameters below 1/8".
★HIGH HARDNESS: Made of high-quality alloy spring steel and hardened to HRC 44-48 and all critical surface is precision ground.