Different way of referring to the trim levels and whether the trim is an auto or a manual. The fifth character in the VIN identifies the trim, both 2012 and 2013, and uses the letters. The G would be for the auto RS and H for the manual RS. In 2012, not in the VIN, the numbers 1 and 2 were used to identify manual vs automatic transmissions. ie: 1LS and 2LS, 1LT and 2LT and 1LZ and 2LZ.
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