Excuse me? oh right, ...nolders..... sounds fancier than Gurney Flaps but that's precisely what they are, named after Dan Gurney who invented them in the early 1970's.
Anyway in this animation from Gazzetta dello Sport we see how no detail is too small when it comes to F1 aero developments. What's described is the revised front wing Ferrari is expected to use in Australia with its main features being the additions of the sawtooth nolders to maximize downforce at medium speeds and additional longitudinal flaps to minimize turbulence.
Perhaps more learned readers will chime in but I believe the sawtooth part has to do with managing how the boundary layer flows and turbulence.
The detail and shape of this year's Ferrari front wing just amazes me. Moving sculpture.
On a side note, if you are a Renault fan, Flavio Briatore will be in a live VideoChat on the Gazzetta web site starting at 9:30 am EST, 15:30 European time.