When I first stated building my bike, I built an air box for it.
Ended up with pods, but may install this beast on another project.
It is a K&N style filter and part of the installation parts for a 1999 Suburban with a 454.
It is a hexagon tube that is made for holding welding rod. Cut holes in the side of it and installed stock rubber boots.
I'm sure thet same design could be used with a much smaller air filter, but it's what was hanging on the wall at the time.