The USS Alka-Selsior (NCC-1404) was a 23rd century Federation starship operated by Starfleet.
In 2368, the Alka-Selsior was one of the many decommissioned ships stored at Surplus Depot Z15 in orbit of Qualor II. (TNG: "Unification I", "Unification II")
This studio model was one of the concept models designed for the USS Excelsior for Star Trek III: The Search for Spock. The name was an in-joke reference to the Alka-Seltzer brand-name of indigestion medicine, and a play on the name Excelsior.