Sanitary Non•Pressure Sight Glass Manhole is a hygienic integrated access and observation device specially designed for normal pressure sterile production systems. This manhole combines manhole maintenance access and sight glass real-time monitoring functions in one, requiring no pressure-resistant structure, which simplifies the overall equipment design. It is made of high-quality SS304/SS316L stainless steel with seamless mirror polishing, completely free of sanitary dead corners, residue and dirt accumulation, adapting to CIP automatic cleaning and high-temperature sterilization. The transparent sight glass enables operators to directly observe the internal reaction status, liquid level and material operation of the tank body. It is widely used in various normal-pressure sanitary storage tanks, mixing tanks and fermentation equipment in food, beverage, pharmaceutical and cosmetic industries.