Centaur Precision Tools ER Sealed Coolant Rigid Tap Collets can be utilized for synchronous tapping operations using any ER collet chuck. The Collet bore is exact tool diameter, with square drive, for accuracy and rigidity. These ER Sealed Coolant Tap Collets are sealed for coolant-through applications. All Centaur ER sealed coolant tap collets are manufactured from high-grade spring steel, hardened and ground with 100% quality inspection. Centaur Precision ER Sealed Coolant Rigid Tap Collets conform to DIN6499A.