Shower valve on supply pipe

[Jim50505]

Hi,
I just bought an old house that was renovated in the 1980s. The bathroom shower has some kind of valve on the supply pipe - does anyone know what this is for? The whole bathroom will be going into a skip in a few months but I’m just curious as to what it’s for.

Thanks.

 

[exedon2]

Just a shut off valve
Wouldn't bother touching it!

 

[Jim50505]

Just a shut off valve
Wouldn't bother touching it!

Just a shut off valve
Wouldn't bother touching it!

Thanks, it doesn’t move I have already tried it