12Mm I.D. Hsk-40E Guhring Shrink Fit Holder With Conventional Or Mql Coolant, 90Mm Gage Length Hsk-E To Iso 12164-1 / Din 69893-5 With Access Hole | Balanced To G2.5 / 25,000 Rpm | For Tool Shank Tolerance H6 | Includes Setting Screw, Series No. 4977 Or 4904 | For Conventional Cooling Order Coolant Supply Set, Series 4949 Separately | Suitable For Tools With Internal Coolant. A Gripping Principle: When Shrink Fitting Tools Into Shrink Fit Chucks, The Decisive Factors For Ensuring The Safe Clamping Of The Tool In The Tool Holder Are Solely The Heating And Cooling Of The Tool Holder. The Heating Process Expands The Shrink Fit Chuck Enabling A Tool To Be Inserted Or Withdrawn Respectively. During The Cooling Process It Contracts Again And Clamps The Inserted Tool With Maximum Clamping Force. Series No. 4737, Order Code 012.0400. Made In Germany, Guhring Part #9047370120400