Sewage clarification systems and devices; systems and devices for water supply, water distribution and water conduit; water filtering devices and water filters; parts for the aforementioned systems, namely pumps for water supply systems, water conduits, accouterments (cocks and valves), mixing batteries for water conduits, water containers and service water containers (not made of metal and not made of brick work), filter containers, sand filters, multilayer filters, accouterments for inlet and outlet, water aerators, disinfection and sterilization apparatus for sewage systems and thereof consisting installations; the aforesaid goods only in the field of waste water treatment installations for commercial vehicle washing

Gravel, silica, filter gravel