The guys took THEIR HATS off. What did you think I was talking about?

Here's one of the ONLY times, you'll get to see Zac Brown without his trademark knit hat while they opened up the NHL Winter Classic singing the National Anthem at 'The Big House' in Ann Arbor, Michigan in front of 104,000 hockey fans and on National tv. 

Wonder if Zac paid NBC off to skip the close up shots during the performance.