J has two of them (a few years apart).
They have changed a little over time. If that matters (and it probably does for modern OSes), on should check:
http://www.everymac.com/systems/apple/macbook_pro/macbook-pro-unibody-faq/differences-between-macbook-pro-mid-2012-late-2011.html
http://www.everymac.com/systems/apple/macbook_pro/macbook-pro-unibody-faq/
Cheers,
Scott.
They have changed a little over time. If that matters (and it probably does for modern OSes), on should check:
http://www.everymac.com/systems/apple/macbook_pro/macbook-pro-unibody-faq/differences-between-macbook-pro-mid-2012-late-2011.html
http://www.everymac.com/systems/apple/macbook_pro/macbook-pro-unibody-faq/
Cheers,
Scott.