Twin-head condenser discharge spot welder adopts tandem welding method, solves difficulties in welding of workpiece with coatings like paint, polyester protection film on its surface . It also applies to workpiece without coatings and those connected with thick and thin pieces . For exceptional metal part with coatings on double surfaces, other metal accessory can also be welded on it with this method. Suitable for single surface, single spot and single surface ,double spots weld. One surface free of damage is achievable .