https://www.mstnland.com/products/wafer-type-butterfly-valves.html
WAFER TYPE BUTTERFLY VALVES
NON-PIN CONCENTRIC BUTTERFLY VALVE
MstnLand's series of New non-pin concentric butterfly valves can be widely used in the clean water system of municipal pipe network, water heating system, construction and other industries, which can not only quickly connect or cut off the medium, but also quickly adjust the medium flow and can be used in noncorrosive medium pipeline or equipment, for closure, connection and flow regulation.