was an early 1970s progressive hard rock band from Berlin, Germany. Their only album, Dirt Box , was released in 1971/1972 and has since gained cult status, largely because it inspired the title of the acclaimed 2001 album by the Swedish metal band Opeth.
The "JPN (Bm)" in your query likely refers to a specific of this album (often issued by labels like Belle Antique) or a high-quality digital backup (like a Blu-ray or bitstream rip) of a Japanese press. Guide to Blackwater Park's Dirt Box 1. Band Background & Style BlackWater Park - Dirt Box JPN (Bm)