wavin is a pipe manufacturing plant that started operating in the Netherlands in 1955, and the cap apparently intended for it marks 50 years of its existence
STĄPORKÓW - a city in Poland ZELIWO KANALIZACYJNE - Iron sewer
This cover was also photographed in 2023 in Warsaw, Poland by McCartney - Wąwozowa 4, 02-796 Warszawa, Poland Click for a larger image