VFD-21 Finish: Black, Rack Height: 36. 75" H (21U Space) Features: -Compatible with DWR Series rack units - select compatible space rack height. -UL Listed. -Can be installed with left or right swing. -Doors are equipped with a cam keylock. Product Type: -Ventilation. Product Type: -Front Doors. Lifestage: -Adult. Dimensions: Rack Height 17. 5" H (10U Space) - Overall Height - Top to Bottom: -17. 5 Inches. Rack Height 21" H (12U Space) - Overall Height - Top to Bottom: -21 Inches. Rack Height 28" H (16U Space) - Overall Height - Top to Bottom: -28 Inches. Rack Height 31. 5" H (18U Space) - Overall Height - Top to Bottom: -31. 5 Inches.