The left endplate for the rear wing was a bit bent from the incident last year, so we’ve upgraded to the latest spec endplates. Thanks to Warren at Radical Australia for getting these to us so quickly. Looks good, and hopefully works even better!
Old:
New:
DBS Motorsport 
any idea on what the difference is for? Low speed or high speed corner stability? Less straight line drag?
Not sure to be honest mate! After some research it seems like this is the popular theory:
Wing endplates act as span increase aerodynamically. That is, in general terms, a wing with an endplate is equal to a wider wing with out one.
That would explain the rear wing of a Stohr WF1. The wing end plates are so big they connect to the rear quarters.
They’re also connected on the AUDI R18, so there must be some benefit in it. The only question is why they didn’t do it in the first place??