The Joyo JF-319 Green Legend is exactly what it sounds like....an improved TS circuit copy. A cleaned up, less mid rangy muddy version of the original classic overdrive sound that screams. Except now it's a third of the size of the original. And lighter for those who like light weight gigging. The flippable plastic cover is designed to protect your carefully dialed in settings from getting moved around during transport or gigs. Set it and forget it, literally. And it's true bypass of course.