An Observer, Coach/ Trainer assigned to 188th Infantry Brigade challenges Soldiers assigned to 4th Platoon, 376th Postal Company, 304th Sustainment Brigade as the train on proper postal receipt procedures during Mobilization Exercise II (MOBEX II), Jul. 24, 2023, at Fort Stewart, Georgia. The MOBEX was part of 1st Army's Pershing Strike Exercise which validates Mobilization Force Generalization Installations (MFGI) operational and support plans, Soldier readiness processing, and validation of a Global Force Management Allocation Plan (GFMAP).