57th Maintenance Squadron emblem.  Approved 10 April 1981 when squadron was 57th Equipment Maintenance Squadron.
<a href="https://en.wikipedia.org/wiki/United_States_Army_Institute_of_Heraldry" class="extiw" title="en:United States Army Institute of Heraldry">en:United States Army Institute of Heraldry</a>
1981-04-10
<a rel="nofollow" class="external free" href="http://www.afhra.af.mil/About-Us/Fact-Sheets/Display/Article/433261/57-maintenance-squadron-acc/">http://www.afhra.af.mil/About-Us/Fact-Sheets/Display/Article/433261/57-maintenance-squadron-acc/</a>