This is a replacement HeatBreak for E3D-v6 1.75mm HotEnds.
Since v5, the manufacturing processes for all our HeatBreaks has been overhauled to achieve a better internal surface finish than ever before. The improved internal surface finish will help to reduce extrusion force and improve relliability on retractions.
This V6 Heat Break is not cross-compatible with its V5 predecessor. If you are upgrading your V5 Hot End, it is recommended that you also upgrade to a V6 nozzle.