M1156 precision guidance kit
The M1156 precision guidance kit (PGK), formerly XM1156, is a U.S. Army-designed precision guidance system to turn existing 155 mm artillery shells into smart weapons. The prime contractor was Alliant Techsystems – later merging with Orbital Sciences Corporation to form Orbital ATK, in turn being taken over by Northrop Grumman and renamed Northrop Grumman Innovation Systems – and the industry team includes Interstate Electronics Corporation.
Source: Wikipedia — M1156 precision guidance kit (CC BY-SA 4.0)