5 ton pedestal jib used by the US Army Corps of Engineers at the Mississippi Lock and Dam No. 20 in Canton, Mo.
K Q Bremmer
CC BY-SA 3.0
<span class="int-own-work" lang="en">Own work</span> (<span lang="en" dir="ltr">Original text: <i><bdi lang="">self-made</bdi></i></span>)