Question for T really or another Tech.
Is the metal shield over the multijets oil filter necessary?
If so, what is its purpose?
I thought it may be a protective shield (but from what) or to stop the plastic filter housing unscrewing, but seems so unlikely and some cars have a similar filter arrangement with no shield.

I must admit I always fit it back on but like you say I also see no reason for it except possibly heat protection?

Thanks T