This Optimum Series Aneroid Sphygmomanometer comes with a chrome-plated brass air release valve with filter screen, a dip-molded inflation bladder that can withstand daily abuse and a double stitched nylon cuff includes unique marking system to prevent users applying the wrong size cuff on patients. The inflation bulb includes a filter screen end valve which reduces dust build-up. These units also feature a Lifetime calibration warranty.