<a href="https://en.wikipedia.org/wiki/Ceiling_fan" class="extiw" title="w:Ceiling fan">Ceiling fan</a> at the <a href="https://en.wikipedia.org/wiki/O%27Hare_International_Airport" class="extiw" title="w:O'Hare International Airport">O'Hare International Airport</a> in <a href="//commons.wikimedia.org/wiki/Chicago" title="Chicago">Chicago</a>. To improve efficiency, this ceiling fan is equipped with <a href="https://en.wikipedia.org/wiki/wingtip_device" class="extiw" title="w:wingtip device">wingtip devices</a>.
<a href="//commons.wikimedia.org/wiki/User:Dllu" title="User:Dllu">Dllu</a>
<span class="int-own-work" lang="en">Own work</span>