ER collets are a type of tool holding system commonly used in machining and milling applications. The term "ER" stands for "Elastic Region," indicating the collet's ability to expand and contract within a certain elastic range. ER collets are used to secure cutting tools, such as end mills or drills, in the spindle of a machine tool. Chouhan Mechanics Pvt Ltd  is the provide every sizes of ER Collects as they want .