Anti-flood devices protect interiors from flooding caused by sewage backflow. Karmat non-return valve 50mm is an ideal solution where it is impossible to install a non-return valve to protect the whole building e.g. in an apartment block. Advantages - flap cover, and all fasteners (screws, nuts, washers) are made of chromium-nickel stainless steel type 0h18n9 - the non-return valve is made of ecological polypropylene, a non-toxic material, resistant to corrosion and chemical agents - to produce gaskets the highest quality of flexible materials with increased resistance to weathering and aging, have been used - Non-return valves 50mm meet requirements of the standard EN 13564-1 and they are marked with the CE mark. The design is registered in the Patent Office. Features: - Installed onto sewer pipes 50mm The non-return valve ø 50 in version A is fitted in the horizontal course of ø 50 sewage pipework attached to the wall by means of brackets. A non-return valve installed in such a way can protect several facilities at the same time if they are connected to the same sewage system such as a bath or shower base traps.