The Omega ER20 Collet is a coolant-sealed, standard-precision tool holder designed for secure mounting of round-shank tools in CNC milling. With run-out under 10 microns, it delivers reliable, repeatable results across a clamping range of 3–13 mm, making it ideal for engineers, machinists, hobbyists, and workshop teams who need predictable performance.

Newer versions have no rubber seal on the nose, and the design uses non-overlapping longitudinal slots to help prevent coolant loss.

• Ultra-low run-out for precise milling: keeps tool position stable within under 10 microns for tight tolerances and smooth finishes.
• Coolant-sealed, leak-resistant design: non-overlapping longitudinal slots prevent coolant from leaking at the nose, with the newer, rubber-seal-free nose for consistent performance.
• Wide 3–13 mm clamping range for round shanks: accommodates a broad range of tooling sizes with reliable grip; to maintain the seal, use only round shank tooling with no clamping flats.

This combination of precision, coolant containment, and flexible sizing helps you streamline your workflow: fewer tool changes, cleaner machining environments, and more consistent results across jobs. Whether you’re dialing in fine aluminum finishes or taking on tougher materials, this ER20 collet provides dependable holding power and predictable performance, helping you complete projects faster with less rework.