The Xtra Wide Presentation Cart comes standard with four shelves in gray. GREENGUARD Indoor Air Quality Certified and GREENGUARD Children and Schools . Laptop shelf is height adjustable. Optional shelf mounts to the front or either side of cart. Black powder coated steel frame includes 4-Inch casters (two locking). Optional locking cabinet available. Includes rack mount for standard 19-Inch rack equipment. 10 year guarantee.