The hard rock band Charlies was formed in the mid-1960s in the city of Lahti in Finland and was the country’s earliest and most authentic underground band. The founding members were guitarist Eero Ravi, singer and harmonica player Wellu Lehtinen, bassist Kari Lehtinen and drummer Ari Ahlgrén. Initially, they performed mainly as a blues rock band, drawing inspiration from British acts such as Cream, the Jimi Hendrix Experience and Led Zeppelin. With saxophonist and flautist Igor Sidorow as the fifth band member, their hard, bluesy rock sound later became significantly more progressive. The quintet now played energetic hard prog and heavy psych, characterized by loud fuzz guitars, dynamic flute interludes, distorted saxophone and screaming vocals.

They toured Finland and Sweden extensively and successfully, often up to three times a week. In 1970, the band recorded material for an album at Microvox Studio at their own expense over the course of two days and took these recordings to Love Records, the only label that also released music by non-commercial and unknown bands. Their debut album Buttocks was then released in December 1970 in an extremely limited run of just around 300 copies, but went completely unnoticed. This made this killer album one of the rarest and most valuable records from Finland. And a real heavy one!