This is ER16 High Quality Collet with 3.5mm Hole.
Specifications:
  • Made from Alloy spring steel and fully hardened
  • All critical collet surfaces are precision ground for accurate fit
  • Works in all ER16 Collet Chucks
  • ER16 collet has a full 3.5mm range of collapse while maintaining full accuracy
  • ER16 collet has a range :  3.0mm to 3.5mm