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The 12-inch single (often called "12") is a type of gramophone record that has a wider groove compared to other types of records. This allows better sound quality. This record type is used a lot in disco and dance music genres, where DJs use them to play in discos or clubs. They are usually played at 45 RPM, which allows for improved quality.
fr:Disque microsillon#Douze pouces (30 cm)