Aluminum Ladder Tray Width 18 in Height 5 1/4 in Load Depth 4 in Material Aluminum Length 12 ft Capacity 75 lb / per ft 12 ft span Finish Unfinished Includes Splcie Plate / Hardware Kit Standards NEMA 8A-12B UL Flange Width 13/16 in Mounting Hole Diameter 1/2 in Rung Spacing 9 in Weight 20 lb