Everbilt 48 in. x 3/4 in. x 1/16 in. Aluminum Square Tube 801317 - The Home Depot
Amazon.com: METALLIXITY Square Aluminum Tube (20mm x 20mm x 2mm x 200mm) 3Pcs, 6063 Aluminum Tubing - for Home Furnishing, Machinery : Industrial & Scientific
2" x 1/8" Alum Square Tube 6061-T6-Extruded | Online Metals