Pro-Series High Accuracy ER-16 3/8″ Spring Collet (3901-5159) ~ AA Grade. ~ 5 Micron. ~ Superior finish. ~ Runout is less than or equal to .0002″. ~ Made of high grade SUJ2 steel. ~ Hardened and precision ground to 44-48HRC. ~ Exceeds Federal Specifications. ~ Major diameter is .670″. ~ Overall length is 1.052″. ~ Inside diameter is ground to reach mirror finish increasing grip force. ~ Surface treated to reduce rust and improve hardness. ~ Cryogenic treatment to significantly increase wear resistance. ~ Collet must be assembled into collet chuck nut before inserting into the collet chuck. AA Grade. 5 Micron. Superior finish. Runout is less than or equal to .0002″. Made of high grade SUJ2 steel.
