ASTM D6927, D5581 and D4867 Microprocessor-based control for precise temperatures throughout the range. Includes a stainless steel shelf, which stands 2" (51mm) above the bottom of the unit for free circulation of water above and below test samples aided with the included stir bar. Volume is 14 gallons (53L), and dimensions are: ID: 20" W x 20" D x 10" H (508 x 508 x 254mm).