MT2 ER25 Collet Chuck Tool Holder Set 15 Pcs ER25 Collets Holder Taper: Morse Taper 2, MT2 Alloy steel and hardened to HRC 60-62. Tested T.I.R: 0.0001" Back Bar Thread :M10 x 1.50P 1 MT2 collets holder, 15Pcs ER25 collets, 1 wrench Collets Size (in inch): 3/32, 1/8, 5/32, 3/16, 7/32, 1/4, 9/32, 5/16, 11/32, 3/8, 7/16, 1/2, 9/16, 19/32, 5/8