The back pad also fits in with Gretsch's fondness in the '50s and '60s for gimmickry in general. For example there's the weird Floating Sound Unit bridge, sometimes referred to as the Tuning Fork bridge, used on some late '60s and '70s Gretsch hollowbodies. Invalid Link Removed Or the built in string mufflers used on some models. A lot of this stuff came from the weird brain of guitarist Jimmie Webster, a Gretsch endorser and product demonstrator who released a method book for fretboard tapping several years before Eddie Van Halen was born.