Sag Harbor Industries, Inc | Coils | Cable Assemblies Thomas Edison's son Charles, founded Sag Harbor Industries in 1946 with one goal in mind: to manufacture electrical coils and inductors of superior quality. Sag Harbor Industries' engineers work hard in understanding the applications of our clients in order to better ensure that the products we make go above and beyond their expectations whether it be an inductor, electric coil or solenoid coil, you can rest assured that the products you get from Sag Harbor Industries (SHI) meet and exceed your expectations.