Proozy offers the Birkenstock Unisex Madrid Birko-Flor Sandals in several colors (Toffee pictured) for $75.99. Coupon code "DN3999" drops it to $39.99. With free shipping, that's tied with our mention from two weeks ago as the second-lowest price we've seen for these sandals. (It's the best deal today by $50.) They're available in select men's sizes from 7 to 10.5 and select women's sizes from 4 to 12. Deal ends May 3.