Welch Allyn Tycos 767 Wall Aneroid Sphygmomanometer Blood Pressure Unit with Adult Cuff. Aneroid sphygmomanometers are widely accepted as an alternative blood pressure unit to mercury devices and their associated disadvantages. This Tycos unit offers precision and a jeweled-movement manometer that is certified to be accurate within one percent of scale (+/-3mmHg). Laser-engraved dial face for precision calibration. Built-in basket for securely storing the inflation system. High-impact housing and bezel to protect the movement and crystal. Large dial face (6.25"/15cm) and bright orange pointer for easy reading. 40 degree side-to-side swivel for clear viewing at all angles. Lifetime calibration and manufacturing warranty.