This will add 25 per-vehicle programming subscriptions to your GM account, allowing you to perform the module programming, setup, and configuration functions available in the SPS application for all modules on each vehicle for a 24 month period. The 24 months timer starts independently for each programming subscription when you connect to SPS for programming for the first time on a given vehicle.  The number of programming events for the subscription cannot exceed the set number of modules in the vehicle.