TE holders feature the minimum gauge length possible in order to provide maximum ridigity while cutting. They also provide added Z clearance and are used with standard ER collets. ER collet chucks handle a wide range of machining jobs without having to buy new tool holders. Simply choose the right size collet for the job, set tool depth and tighten the collet nut and pull stud to the proper torque using a torque wrench and tightening fixure.