Our aluminum rail profiles are extruded from 6063-T6. The aluminum rail is lightweight, and available in 3 profiles (ZRAT, ZRA1, ZRA2) up to spans of 30 ft (9 m). Our steel rail profiles are rolled from 9 gauge, A569 hot-rolled steel. The steel rail is rugged and economical, and available in 2 profiles (ZRS2, ZRS3) in spans up to 24 ft (7 m). For increased spans and capacities our ZRS2, ZRS3 and ZRA2 profiles are available with strongbacking.