Picked this CF fog vent up from The TT shop.
I'm going to attach a collection box/funnel to the back of the vent section for the air ducting to the front brakes,
Fixed today
They insert one end like the original and they supply a screw and washer which goes through the face of the vent in a small recess, which not only looks s**t needs a hole in the bumper! I've fixed them on with number plate adhesive pads and attached a cable tie at the back just in case
Should go well with the other bits coming.
(EDIT) Number plate pads seemed to work well but in the morning felt very loose, might have been the cold weather, have now used silicone mastic for non-porous surfaces.