only compatible with the listed units officially. if they fit another unit by the same OEM etc then i guess, go for it. The range will expand over time.
Also, before anyone asks about superflower. They have a patent on their connectors, which means there is no offering for their units currently.
These are kits for PSUs.
we have extension kits from BitFenix and Silverstone that fit the bill if it is extensions that you want.