Love these guys and used them multiple times to build small structures. McMaster-Carr (obviously) also has a ton of handy connectors and fasteners: https://www.

Love these guys and used them multiple times to build small structures. McMaster-Carr (obviously) also has a ton of handy connectors and fasteners: https://www.mcmaster.com/t-slotted-framing/ https://www.mcmaster.com/t-slotted-framing/