Aluminum Finned Tube Heat Exchanger Aluminum Finned Tube is a single-metal composite finned tube rolled from an aluminum tube, with no contact thermal resistance, high strength, heat resistance and mechanical vibration, good thermal expansion performance, and a considerable extended heat exchange surface. Aluminum Finned Tube Quick Details: Outer diameter (OD): 16mm Min~50.8mm max. Tube length: up to 18,000 mm. Fin height: 16.5mm max. Fin thickness: generally 0.4mm~0.6mm Fin pitch: 2.1mm minimum (12FPI) Surface Protection: Both bare ends shall be zinc or aluminum metallized by electrospray arc system coating. Accessories: Tube support boxes, clamps or spacer boxes (materials: aluminium, zinc and stainless steel).