The Flash 04 vents above the grill are really useful to keep the van ventilated and dry, but a nightmare in the wind.

I used some white packing foam from an amazon delivery, cut it to shape and wrapped it with wood effect fablon to make these. They weigh nothing and take seconds to insert / remove and don’t look awful. Used them for a year now and am well happy.

Top tip... if your grill keeps blowing out in the wind try opening the bathroom vent which means the air flows through the van without flowing through the grill. It's not perfect but it work really well sometimes. 

Shrewd observers will have noticed that the fablon doesn't quite match the van, that because I did it before I found the matching stuff here.