sack of oats
A burlap sack with the appearance of a sack of oats, yet containing a "rocket gun". Concealment of illegal substances such as marijuana or crack in what appears to be a harmless burlap sack.
Officer: Sir, license and registration please, and could you please tell me what is in the backseat of the vehicle.
Bassline: That's just a sack of oats.
Bassline: That's just a sack of oats.