Tanga offers the Nike Unisex Mercurial 8.0 R Sunglasses in Matte Black or Military Brown, model no. EV0783, for $59.99. Coupon code "NIKE10" cuts the price to $49.99. With free shipping, that's the lowest total price we could find by $43. They feature plastic, wrap-around frames.
Groupon offers the Nike Unisex Sporty Sunglasses in five colors (Black/Blue pictured) for $49.99 with free shipping. That's $66 off list and the lowest price we could find. They feature UV protection. Deal ends May 24.