u/Breakshite

Got these steel beams recently. I'm curious if anyone knows what industry they're used in or their specific use case. They're c-channel, tapered at both ends to form some kind of expanded i-beam. Measured along the "I", two of them are 5" tall, one of them is 8" tall. About 30 ft long. The one on the right has a plate with a hole in it at the very end. Is this for bolting to another structural member? Attachment for high tension guy lines? The person I got them from said he thought they were used in transmission towers or running electric lines but wasn't sure.