MDF® Desk & Wall Aneroid Sphygmomanometer - Professional Blood Pressure Monitor The safety, durability, and convenience of the super-duty MDF® 840 make it ideal for high-traffic areas in the emergency room, clinic, or ambulance. With a certified manometer, stress-tested over 3,000 times, and calibrated 5 times, it is one of the most durable, accurate, and dependable blood pressure measurement devices on the market. To reduce the parallax effect, the large scale (15 cm) is imprinted with black-bold dials and pressed with a raised outer rim to achieve accurate viewing at all angles. Doubly protected against shock, the internal manometer is enclosed in a die-cast zinc housing that is cushioned within the external high-impact thermoplastic case. The faceplate can swivel smoothly with a wide range of 180° horizontally and 90° vertically to ensure the gauge is easy to see.