Gastronorm (en.wikipedia.org)

I can recommend the smaller ones such as 1/9 and 1/6 for personal use. Very durable, last decades.

There's an unexpected optical illusion in the size diagram. The 1/6 block appears narrower than the 1/9 block.

Sadly, only the mounting rim is normed. The form of the body is not. Meaning, containers from different manufacturers don't stack necessarily and lids are not interchangeable.