Built-in pots and fittings for GU10 LED spots

Can someone recommend good built-in pots and sockets (swiveling) for GU10 LED spots?

I thought the preparation is done by the home builder? The sockets don't care whether they are swiveling or not.

And I'll give a tip for the next question: Who knows good mounting frames? In that case, it might be important which mounting dimension (diameter) the pot offers and which hole dimension the mounting frame requires.

At our place, the Spelsberg IBTronic XL H 185 F junction boxes were installed. Unfortunately, I can't say much more about them, except that the things made a good impression. The cost is 25 euros on Amazon. Ours cost about 40 euros including installation.