1. BT 40 ER Series Collet Chucks. Kingston: Balanced to 15,000 RPM @ g6.3. Spin Tru: Balanced to 20,000 RPM @ g2.5. Manufactured to ISO9002 quality control standards. Each holder balanced on a HAIMER Balancing machine (certificate included). Accuracy: 0.0002” TIR or better. Taper cone circularity per AT3 specifications Our Products:- BT 40 ER Series Collet Chucks CAT 40 Toolholders CAT 40 Endmill Holders CAT 40 ER Series Collet Chucks CAT 40 Jacobs Taper Holders CAT 40 Morse Taper Holders CAT 40 Shell Mill Holders CAT 50 Endmill Holders CAT 50 ER Series Collet Chucks CAT 50 Shell Mill Holders BT 40 ER Series Collet Chucks BT 40 TG Series Collet Chucks BT 40 DA Series Collet Chucks BT 40 Jacobs Taper Holders BT 40 Morse Taper Holders BT 40 Keyless Drill Chucks BT 40 Shell Mill Holders Tension Compression Tap Holders Rigid Tap Holders Location:- 411 W. Monroe St,Austin, TX 78704 USA Phone:- 714-722-1656 Email:- sales@exacttooling.com Website Url:- https://exacttooling.com/pages/milling-toolholder-bt40-erseries/