Casting 3 Way Stainless Steel Square Tube Connector - China Casting, Die Casting | Made-in-China.com
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Tube connection with joint, square tube - Railing parts - Marifix
Amazon.com: CONNECTOR RIGHT ANGLE FOR SQUARE TUBE JOINT 2 WAY PIPE PROFILE PLASTIC 20MM 25MM 30MM 20x20 25x25 30x30 (A=20 x L=36 x L1=36 x t=1.5) : Industrial & Scientific