It's shaped like this:
but has a different symbol on it...
something like a fancy lower case "h" with a slash through the top of the h...
i've seen 2 people wearing them... one wouldnt tell me what it was, the other said it was APO (but i looked up their pledge pin and it didn't look like the one pictured)
just curious... (if it helps, ive seen both a girl and a guy wearing this pin)