What brand and model of sunglasses does Peter Sarsgaard wear in the movie An Education?

There's no definitive answer readily available online specifying the exact brand and model of sunglasses Peter Sarsgaard wears in *An Education*. While numerous websites discuss the film's fashion, they don't pinpoint the sunglasses' details. It would likely require frame-by-frame analysis of the film and possibly contacting the film's costume designer.