This video shows a overview of the Huma Air high flow dual hole transfer port and its features .

NOTE :
As for now the matching pellet probe is only available for the FX Impact . In the future the Crown and Dreamline should be available as well.
The transferport itself as metioned in the video can be used for every FX Airguns barrel on the Impact , Crown and Dreamline.

Huma air website :
https://www.humaair.com/HighFlowDu...