️Oakley Flak® 2.0 XL – Polished Black / Prizm Field. Oakley Flak® 2.0 XL Sunglasses (OO9188-9159). Why Choose Oakley Flak® 2.0 XL?. The Flak 2.0 XL brings sharp style and serious function together. With extended lens coverage for better protection and a secure, no-slip fit, these sunglasses are ideal for athletes and active individuals.