Serial Do Mount&blade How Do I Find The Serial Code For Sims 3 When I Direct Downloaded It From Ea Manager?

How do i find the serial code for sims 3 when i direct downloaded it from ea manager? - serial do mount&blade

Where can I find my serial code for the registration of Sims 3rd (I download directly from the EA Download Manager, so I have a box with the code on the back.) In The Sims 3 website i need the serial number so that I can change that.