Flag of San Juan Province, Argentina.
Government of San Juan <br> (Vector graphics image by <a href="//commons.wikimedia.org/wiki/User:Guilherme_Paula" title="User:Guilherme Paula">Guilherme Paula</a>)
1911
SVG based on <a rel="nofollow" class="external text" href="https://www.argentina.gob.ar/sanjuan/simbolos">this</a>