TX-664-3 Mk 70

The caption reads, below the dimensions:
"The Mk 70 Mod 1 motor is an upgraded version of the US Navy's Mk12 Mod 1. It is the booster for the Navy's two-stage, extended-range RIM-67 Standard Missile SM-2ER used primarily as a fleet protection system against enemy aircraft and missiles."
ATK (formerly Morton-Thiokol) outdoor display in northern Utah, USA. This was a major rocket development facility during the Cold War and beyond.