ER straight shank 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 to proper torque using a torque wrench and tightening fixure. Use "PowerCOAT" nuts to increase the holding power and safety of your tool holders. High holding power extends cutting tool life and improves surface finish.