two parts - one is the main cover part no- 3B2 819 447
Battery cover- 3b2 819 422
just check what hole you want for the brake res though as some are round and some oval?...
heres the pics of where you need to cut it to fit your B5
you will also need to adapt the rubber that clips onto the front , get a screwdriver and bend the insides to make it wider and it will now have to clip onto this also
ant