[e.lamberson]

The attachable mentioned will not work on the sero plan because it is an old plan and it has been replaced with the everything program. I would imagine the code could work with the plan however its a matter of getting someone who would add this to your account. The customer care rep did say however that someone could change from the sero to the 500 everything for 60 dollars if they wanted. This would give someone TV, Nav, and Radio. If you subscribe to Nav and TV though it would be 9.99 for Nav and 9.95 for TV Premier. So even with the old sero and the two additionals it would still be cheaper that the 500 everything. Hopefully this helped.