Half or full steel stud

[Oldfart]

The vague headline refers to the metal studs in the hardware store being joined together in pairs, thus forming a "whole" square 45x45 stud. It could be taken apart and then I would have two identical U-profiles. The receipt stated 4 studs instead of the two I expected. What I perceived as two studs were actually four.

So now I'm wondering the following:

Is half a stud a whole stud or is a whole stud two halves? (Without a bad pun; Is a U-profile a complete stud or should they be joined together?)

If you put them together, it becomes two layers of metal. How much better do the self-drilling drywall-on-metal screws attach to two layers of metal compared to one?

 

[b8q]

A solitary U-profile is a complete rule in itself.

 

[sdrlnd]

A profile consists only of "one" layer of sheet metal. You should not use them as double; it is just an unnecessary cost as they are made to be mounted one by one. The screw attaches adequately to a stud.
//Oscar