an intangible card, of which, each bro has two of. When a bro needs something, and pulls a bro card, his bros must help him in any way possible, despite their previous obligations, warrants, etc. If a bro uses more than two in his lifetime, he is considered a tool
Mark: I need you to wingman for me. Sally is bringing her friend.
Joe: I can't, bro, I have a bowling match.
Mark: I gotta pull a bro card on this one man.
Joe: Ok, i'll tell the captain i cant make it.