uxcell 50Pcs M3x6mm Internal Hex Socket Set Grub Screws Cone Point 304 Stainless Steel Screw...

These M3 screws are tiny! As their name indicates they are 3mm in diameter. The hexagonal hole for inserting the hex tool is just 1.5 mm in size. These "Grub Screws" would be good replacements for a knob set screw, but I can't think of much else I could used them for. I ordered these because they were suggested to be used with the uxcell M30 L-bracket. They cannot be used with this L-bracket and they are much too small. So if you need a knob set screw, that has metric threads, this is what you need.

I was really happy to find the rare shorty 3mm length in an M4 thread, glad ZeeBooth had these in stock. These are just mediocre quality, however. All 50 were present but about a dozen of them were unusable rejects and probably a third of them had off center or flattened points. General finish, broaching, and threads appeared good, though. I only needed sixteen of them, so I'm happy enough. These are available SO much cheaper if you order them directly from overseas but ZeeBooth had them to me fast enough (Prime, although it took a full week...?) and I can't find them locally. If you need most of the bag, consider ordering two or three and picking out the quality ones I guess.

Most work well, but if you really need exact specs, be prepared to toss about 1-2 in 10. I had plenty, so wasn't a big deal, otherwise worked well.

They threaded in, did the job, prices right, all good thanks!

Great replacement part. Adding the rest to my stockpile of nuts and bolts.