What does bro tan bro tan mean?

bro tan bro tan meaning in Urban Dictionary

after that tan you get in your feet for broing down an excessive amount of and wearing flipflops everywhere you go. The tan a bro gets after wearing a container top/bro tank under the sun for an extended period of time. The greatest 'bro tan' could make a bro seem like he could be wearing a light tank top with erect nipples as he is, indeed, shirtless.