NOT FOR USE WITH PLA
The "Jet" for our SE300 / HE280 hotend is only intended for the use of higher temp materials such as nylons and polycarbonates. High temp materials such as these do not need the PTFE liner to reach nearly as far into the heat break as PLA and ABS do, so to allow these materials to print even better we've designed this jet to move the liner UP and away from the heat break while increasing the melt zone.
To install, you will need to remove the top mounting PTC adapter of the SE300 / HE280 and thread this jet in place then reassemble the PTC adapter. The detailed picture shows in red the jet installed in the hotend.