McKesson Mayo Instrument Stand provides additional support during surgical procedures. It features a stable base and a height that comfortably adjusts to either a sitting or standing position. Casters provide additional mobility. The "California-base" style features a double post for better supported positioning of the stand. California-style base for easy positioning 1 inch chrome-plated steel tubing Two, 2 inch rubber wheel, ball-bearing casters Removable stainless steel tray: 19.25 inch x 12.62 inch x .75 inch Adjustable height from 34 inch to 53 inch 20 Inch Base.