Simpsons Duff Logo T-Shirt Duffman! Oh Yeah! Now you can dress with a t-shirt that displays the simple logo of..the Duffman! With "Duff" printed on the front of this red t-shirt within a white rectangle with black writing it is the perfect shirt that even the Duffman would be jealous of. Love that Duff Beer, or just love beer, this shirt will get you saying..Mmm...Duff!