How to Find your Mac's Model ID number

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How to find your Mac's Model ID number?

For Snow/Leopard
Click the Apple icon in the top left corner of the

desktop, About this Mac, and then More Info...from here you will see
the "hardware overview" on the right hand side of the page. Line #2 is
Model Identifier.

For Lion / Mountain Lion
You will have 1 more step to click "system report..." button
in the About This Mac overview window. Line #2 is model Identifier.