Recently I found this very cheap (40 EUR) Thomann Millenium E-Drum Set paired with an Alesis DM5 Sound Module on a local advertising platform. I could not resist. The drum kit turned out to be really cheap in every sense, one of the clamps to hook up the pads broke right away when I tried to tighten it.
You can find these rack clamps in the Thomann online store described as "Millenium MPS-100/200/400 Rack Clamp Tom". They are similar to those sold with Alesis, Classic Cantabile and even Sonor drumkits, I believe the manufacturer is the same. The clamps are made of plastic, wrapping a metal ring with a threaded pin attached, like shown in the image above. This pin just went off its hole in the ring.
But there is a simple solution to that. You could weld it, but that's nothing I can do here. So I took some M6 standard threaded rod (M6 Baumarkt Gewindestange), drilled into the hole of the ring with an M5 metal drill to make it a little deeper and made use of an M6 thread tap (M6 Gewindeschneider). Now I could simply thread the rod into the hole. Add some thread glue if you like.
I guess all of the other clamps will break sooner or later, but this is the workaround. This is a really cheap Drumset but still it's much fun to use it for various tasks in the studio.