Coolant Channel Thru Collet seals coolant from the slits on the collet body and coolant is channel thru the internal bore to directly splash onto cutting tools. All ER Jet Coolant collet has 4 channels that is precision cut out with engineered width and depth to deliver optimal water pressure while not losing the grip on the tool shank. The full length of the shank should be inserted into the collet to prevent potential leakage Robotic Automation in Manufacturing We optimize our manufacturing workflow for both efficiency and accuracy by utilizing robotic arms to load and unload ER collet stock into the Shigiya CNC grinders which are made in Japan. Combining the robotic arms with a reliable CNC grinder is our formular to control tight tolerance in a mass production environment. - ER coolant collet does not have a collapse range, gripping onto undersized shank would introduce leakage - Made in TAIWAN - Conform to DIN6499B