PC Version Download contains 2 Keys. - Keys can be Copy & Pasted into Origin - Battlefield 3 LE Key: XXXX-XXXX-XXXX-XXXX-XXXX - Premium Service Key: XXXX-XXXX-XXXX-XXXX-XXXX
The 1st key contains Battlefield 3 Limited Edition, and Back to Karkand map pack. The 2nd key contains Battlefield 3 Premium Upgrade, and all Expansion packs, and all extras.
I already owned Battlefield 3 Limited Edition when I purchased this I used the "Premium Service Key" to upgrade my BF3 to Premium, it worked perfectly just opened origin, clicked on Origin Menu, Chose Redeem Product code, pasted my code, and Viola, I have everything.
I pasted the "Battlefield 3 LE key" into my Son's Origin, and he now has BF3 limited edition, and the Back to Karkand Expansion.
All this costed me the same price as the upgrade alone.