One of the most popular GM factory keyless entry remotes is a 3-button keyfob with FCC ID LHJ011. One of the vehicles that used keyless entry systems with this remote was GMC Sierra pickup trucks, which used this remote for 2003-2006 model years.
See 3-button GM remote with FCC ID LHJ011 at this link.
When talking about GM remotes, we always like to remind readers that, if you are buying a replacement remote for your GM car or truck, you have to be very careful about the specification. GM used many look-a-like remotes that are not interchangeable. They also were not shy about changing systems in the middle of a model year. If your GMC Sierra is a 2003-2006 truck with a factory-installed keyless entry system in it, then the LHJ011 remote is correct, but before 2003 Sierras used similar looking remotes that are functionally different.
All 2003-2006 GMC Sierra trucks are user programmable applications.