Proozy offers the Birkenstock Unisex Madrid Birko-Flor Sandals in several colors (Toffee pictured) for $57.99. Coupon code "DN39" drops it to $39. With free shipping, that's $11 under last month's mention and the lowest price we've seen. (It's the best deal now by $20.) They're available in select men's sizes from 5 to 9.5 and select women's sizes from 6 to 12.