Cressi Mini SPG GaugeThe Cressi mini pressure gauge is a small, light weight gauge that has been specifically designed to avoid excessive strain on the HP hose that connects to the first stage of the regulator. The instrument has a metal case in chromium plated brass and is therefore extremely strong. The front glass is made so that it also acts as a pressure relief valve. In the event of a sudden increase in pressure inside the instrument, the glass rises slightly,