P38A General observation/query

Hi all, after a brief but calamitous tete-a-tete with a Vauxhall Corsa I've had to swap my front bumper for one that looks all together more RR-ificated.
The one I've just bought didn't have front fogs (like mine) but where my '96 has 2 blanking plates in the holes where the fogs live, the new one (from a W-reg) had a blanking plate on the offside but the nearside was more of a grille-type affair, same shape and mounts.
Just wondered if anyone knows what prupose the grille serves/served.

The grill is to let air through to the oil cooler on a auto diesel .

As above there will be a small radiator behind that grill that coolant from the auto box passes through to be cooled

Thanks Gents, question answered