To show the "Roc Sign", the diamond-shaped hand signal made popular by Jay-Z and others associated with Roc-A-Fella Records and/or Rocawear.
I saw them throwing a Roc before they opened fire!

"Niggas throwin' Roc signs outside of ya Coupe" - Jay-Z, Dig a Hole
by Justin M. Wilson March 4, 2008
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