I have a Harbor Freight “porta power” that works very well. Unfortunately Harbor Freight doesn’t offer a hollow jack for this tool. I've searched for a standard for quick-connect fittings to no avail. I don’t think the quick connect fittings are compatible between brands. Anyone have any experience in retrofitting other brand jacks to a Harbor Freight?
Yes. I do it on the regular. Don't ask me about what fits what and where though. I have been collecting fittings and what not for years.
I found an old posting that said BlackHawk B69477 1/4" half couplers were interchangeable with Harbor Freight pumps. It's worth a try.