What standard sizes are available for ER collets?

The most widely used ER collet sizes in precision machining and workholding are ER16, ER20, ER32, ER40, and ER50. These primary configurations cover standard cylindrical clamping requirements from 1 mm up to 34 mm. The ER16 and ER20 series handle smaller tool shanks and electrode blanks, ER32 serves as the industry standard for general CNC milling and turning up to 20 mm, and ER40 and ER50 accommodate large-diameter stock and heavy-duty cutting tools requiring high gripping torque. While specialized micro-machining series like ER8 and ER11 or intermediate sizes like ER25 also exist in the market, ER16 through ER50 represent the core standards across manufacturing facilities.

MaxxTooling offers collet chucks for the most commonly used sizes in the industry. Visit our website to see our full line of collet chucks.