The stainless steel rear-entry liquid-filled pressure gauge is an instrument used to measure fluid pressure. It uses a back connection, and the connecting thread uses the back of the pressure gauge. It is generally suitable for installation below the waist of the human body, so that people can see the surface comfortably by bending slightly. The pressure gauge is filled with oil, generally swill or silicone oil. Swill or silicone oil is not easy to deteriorate and does not harm the human body surface. The oil filling acts as a buffer so that the pointer can swing smoothly without being subjected to too much impact, affecting the accuracy of the data and avoiding damage to the pointer. This oil-filled pressure gauge is generally used on high-pressure fluid media; the stainless steel shell has enhanced corrosion resistance, which can make it not easily damaged when used in harsh environments.