ER8 Collets – RD8 Collets The ER8 Collet /RD8 system are standardized and manufactured as per DIN 6499 standard guidelines and are truly interchangeable. This becomes important to users that may have toolholding systems from different Toolholding System Manufacturers. Lexis RD 8 Collet / ER8 Collets are designed to collapse with 0.5mm or .0019. Sealed Collets for coolant through applications do not have a collapse range, and must be used at exact size. Lexis RD 8 Collet / ER8 Collets metric sizes starting from 1mm Dia to 5mm with 0.5mm incremental. Lexis ER 8 Collet RD8 Collet ER8 Collet ER Collets ER8 Collets ER8 Coolant Collet ER8 Sealed Collet ER8 Tap Collet ER8 Tap Sealed Collet