In addition to the fuzing function it provides a GPS guidance package and control surfaces to correct the flight of the shell.

The PGK fuse can be screwed onto existing M549A1 and M795 projectiles, be fired from M109A6 Paladin and M777A2 Howitzer artillery systems, and hits within 50 m (160 ft) of the target at any range.

Its GPS receiver compares the PGK's flight pattern to the coordinates of where it should hit, and the fins adjust its path to match where the round will actually impact.

Following fielding in Afghanistan under an urgent materiel release, the PGK underwent First Article Acceptance Tests to verify performance, reliability, and safety.

[11] On 29 June 2015, Orbital ATK announced that the PGK had completed its first production Lot Acceptance Test, demonstrating a median accuracy of less than 10 m (33 ft) and passing all safety and reliability requirements.

[13] In 2021, the U.S. Army plans to produce the upgraded M1156E2/A1, compatible with newer XM1128 high explosive and XM1113 rocket-assisted projectiles to achieve 10 m (33 ft) accuracy at 30 and 40 km (19 and 25 mi) respectively when fired from a 39-caliber barrel.

[14] On 8 August 2013, Australia requested the sale of 4,002 M1156 Precision Guidance Kits with training and associated equipment for $54 million,[15] something unusual for an item still in low-rate initial production.

[18] On 24 April 2018, the US Defense Security Cooperation Agency approved the foreign military sale of 3,500 M1156 kits to the Netherlands at an estimated cost of US$70 million.