The HS728M Hydraulic High Pressure Comparison Pump is a laboratory instrument that generates pressure up to 1000 bar for calibrating high-pressure instruments. It features a hand pump and a booster pump for quick system pressurization and high-pressure point calibration, respectively. The shut-off valve is closed during pre-pressurization to achieve high-pressure ranges. The lead screw allows for precise pressure adjustment, and the transparent oil cup shows the working medium level. The HS728M is widely used to calibrate pressure gauges in laboratories.