Mr. Peter Hayden (or PH and later Enphin) is a Finnish alternative metal band often filed under post-metal, space rock or psychedelic doom. The band was formed in Kankaanpää, Finland in 2000. On their fourth album, Eternal Hayden, the band began to refer to themselves just by their logo, the PH-monogram, leading to confusion what the band should be called. Since then all variations from Mr. Peter Hayden to PH have been used. The group is also part of the Wastement collective.