K & S 1115 Round Aluminum Tube, 5/16" OD x 0.014" Wall x 36" Long, 4 Pieces, Made in The USA: Metal Industrial Wall Tubing: Amazon.com: Industrial & Scientific
Amazon.com: K & S 9317 Round Aluminum Tube, 7/16" OD x 0.035" Wall x 36" Long, 4 Pieces, Made in The USA : Industrial & Scientific
uxcell 6063 Aluminum Round Tube, 300mm Length 16mm OD 13mm Inner Dia Seamless Aluminum Straight Tubing: Amazon.com: Industrial & Scientific
Amazon.com : Jtkens Aluminum Empty Toothpaste Tubes with Needle Cap Unsealed Tube Silver (10PCS, 5ML) : Health & Household