Outwater Mill Finish 1/8'' Inside Dimension Aluminum U-channel 36'' Length (pack Of 4) Alu757-m C-channel in the Furniture Moulding department at Lowes.com
Amazon.com: Aluminium U Profile, 471927 : Industrial & Scientific
Amazon.com: METALLIXITY Square Aluminum Tube (10mm x 10mm x 1mm x 300mm) 2Pcs, 6063 Aluminum Tubing - for Home Furnishing, Machinery : Industrial & Scientific
Aluminium U-Channel for 10mm Glass Shower Screens
Aluminum U-Channel for 10 mm (3/8") Glass - Richelieu Hardware
Source aluminium u channel profile for 10mm glass on m.alibaba.com