Deep Chest Piercing
Deep Chest Piercings are deep piercings passing vertically, horizontally, or otherwise through the chest. It can be as long as three or four inches, and is usually placed either vertically or at an approximate 15 degrees off horizontal. Because the piercing is so long it can take up to a few years to heal. Note that the piercing is only through the skin -- it is not deep enough to actually pass through muscle. It is almost always a male piercing.
This piercing was first popularized by Fakir Musafar who has a pair of vertical deep chest piercings, as well as by Patrick Bartholomew of the London Piercing Clinic who performed many of them, several of which were documented in early piercing videos.