I bought this rectangular tube on Grainger and had it shipped to the local store. It's a great way to avoid shipping costs if you have a Grainger near you. The selection at Grainger isn't as good as McMaster, but the ability to avoid expensive shipping costs makes it my go-to for this kind of stuff. Anyway, this is 2" x 4" x 1/8 wall rectangular aluminum tubing (6063). I cut the angled sides with the miter saw, and trimmed the ends with the bandsaw, then did some cleanup with the sander and scotchbrite wheel.