50pcs T-Slot Hammer Head Nut M4, M5, M6, M8 Zinc Plated Silver Carbon Steel Fastener Aluminum Figure Extrusion Slot European Standard (EU20-M5×10×6)

Nice clean threading and grips very well. Using on 2020 and 2040 aluminium profiles. Hope this helps.

As you would expect for the price some of the nuts are a little tighter than others. But generally ok.

Very low price. Threads are excellent quality. Nuts rotate easily 90 degrees to fully lock into the channel.

Seem fine

great thanks

50 items, all the same. I returned the order!!