An E3B candidate puts on a gas mask during patrol lanes practice at Fort McCoy, Wisconsin, May 10, 2024. More than 150 Soldiers from the Active Army, National Guard and Reserve, try and earn their badge during the E3B (Expert Field Medical Badge for medics, Expert Infantry Badge for infantry, and Expert Soldier Badge for all other Soldiers ) event at McCoy. To earn their badge candidates must demonstrate their proficiency through physical fitness, day and night land navigation, various duty related tasks and a ruck march.