The ends and ferrules are for joining sections of pole for a camp bed .

The connectors are for fairly narrow rods, say 3 to 6mm, so I can make a frame. I want to be able to dismantle it for packing, so some of the joints need to be Quick Release. I've seen some connectors for laboratory tubing ..they're the closest thing I've found so far. Pic below. But surely there's something better out there? 



There are all sorts of choices on alibaba, but they're a bit confusing. I'd probably end up with the wrong sizes or something. And I only want a few...minimum orders of 100 pieces are not what I need!