Is it some kind of isolation valve, how to close it with common tools ?

[tmasa]

Have this under one of the basins, can't find anything similar with google image search ...

Thanks

 

[DP]

It is an isolating valve with broken or missing/ removed lever handle.
try an adjustable spanner

Be prepared for it to leak Same as one on the right

 

[Madrab]

or a pair of pliers

 

[tmasa]

It is an isolating valve with broken or missing/ removed lever handle.
try an adjustable spanner

Be prepared for it to leak Same as one on the right

Thanks

Spanner the nut with one flat side, the elipse thing is static, right ?

Is 1/4 turn required here ?

 

[DP]

Yes to all