Micro 100 QTHM-317 Quick Change Metric Shank Tool Holders, 0.1875&quot; (4.8 mm) ID, 1.063&quot; (27 mm) Head Diameter, 0.750&quot; (19.1 mm) Head Length, 0.6693&quot;(17 mm) Shank Diameter, 0.0001&quot; (0.001 mm) Overall Length