Pronit - probably the youngest of 78 rpm record labels in Poland. It belonged to chemical plants from the town of Pionki (Zakłady chemiczne "Pronit" w Pionkach), where pressing of records was organized in 1957 (but the era of 78 rpm records ended soon, thus the label is better known due to its EPs and LPs being produced until 1990; limited editions production re-launched in 2010). Until 1978, "Pronit" records were pressed using masters of "Polskie Nagrania Muza" and have the same catalog numbers.