This NSK Spindle uses ceramic bearings and is ideal for small diameter drilling, milling, and grinding. A wide selection of collet chucks are available.• Allowable Motor Speed: 50,000 rpm• Spindle Accuracy: Within 1 µm• Standard Size Collet Chuck (CHK-3.175): ø1/8"• Weight: 7.58 oz.• NSK Catalog Number: AS18220 (NR2350)• Repalces older NR-2350 spindle.Included Equipment:• Chuck Nut (K-265): 1 pc.• Wrench (12 x 14): 2 pcs., (20 x 24): 1 pc.Optional Equipment:• Collet Chuck (CHK-[][]): ø0.5 mm~ø6.0 mm in 0.1 mm increments and ø2.35mm, ø1/8", ø3/16", ø1/4"• Chuck Nut (K-265): For Collet Chuck (CHK)• Metal Saw Arbor (KCH-03): For ø0.24" (I.D.) x ø1.18" (O.D.)• Drill Chuck Arbor (DCH-J0K): For Jacob's Taper No. 0• Grindstone Arbor (AGM-03): For grinding wheel with I.D. of ø5mm