Patent #2892371, assigned to Ray Butts, for what would become known as the FilterTron humbucker
Patent #2892371, assigned to Ray Butts, for what would become known as the FilterTron humbucker
Patent #2892371, assigned to Ray Butts, for what would become known as the FilterTron humbucker
Patent #2892371, assigned to Ray Butts, for what would become known as the FilterTron humbucker