ER TAP COLLETS ARE SIMILAR LIKE ER COLLETS AND CAN FIT INTO SAME COLLET CHUCK USED FOR ER COLLETS, BUT IT DOES NOT HAVE COLLAPSIBILITY AND EVERY COLLET COME FOR A FIXED SIZE. 

EVERY TAP HAS A SQUARE AND ROUND SO YOU JUST NEED TO CHECK SQUARE AND ROUND SIZE OF TAP AND ER CHUCK SIZE THAN YOU CHOOSE WHAT COLLET WILL FULFILL YOUR PURPOSE 

Tapping collets will allow user to convert collet chucks used for many purposes into tapping chucks. ER Tapping Collets with Square Drive for synchronous tapping operations using any RD/ER collet chuck. Collet bore is exact tool diameter, with square drive, for accuracy and rigidity. Square in the ER Tap collet is offer tight grip for Tap which reduces slippage in Collets. Available sealed for coolant-through applications, as well as in DIN and JIS standard metric sizes.