Blood Pressure & Pulse Monitor SureSign. Our Suresign Blood Pressure Monitor is intended for the measurement of Systolic & Diastolic arterial blood pressure.. The device measures the fluctuations in the pressure of the cuff produced by extension & contraction of the artery in the arm in response to each heartbeat.. These are converted into millimetres of mercury (Hg) & are displayed as a digital value. This monitor also includes an irregular heartbeat detector & WHO classification indicator.