until 2017, the criteria and conditions under which the "v" device could be awarded differed among the services. for the army, the "v" was worn solely to denote "participation in acts of heroism involving conflict with an armed enemy". for the navy, marine corps, and coast guard, the "v" could be worn to denote combat heroism, or to recognize individuals who were "exposed to personal hazard during direct participation in combat operations". for the air force, the "v" could be worn on the bronze star medal to denote heroism in combat, but also on the commendation medal and achievement medal to denote heroism or for being "placed in harm's way" during contingency deployment operations.