When a woman or girl wears a racer-back or t-back tank top over a regular bra.
This results in double strappage and the bra straps are clearly visible going straight up the back while the tank top has arched straps.
Girl 1: Melissa has racer straps right now.

Girl 2: I know, she does it to show off that she wears bras or something.
by sheabb January 21, 2014
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