Abstract: An improved spot welding system for clamping and welding a plurality of workpieces at predetermined datum locations includes a clamping element, and at least one electrode. The preferred electrode(s) and element are concentrically alignable during engagement, and configured to produce an annular weld about the datum location. More preferably, the workpieces define an opening at the datum location, the element includes an insulated pin at least a portion of which is configured to pass-through the opening, and the electrode defines an inner space configured to receive the portion of the pin, when the electrode and element fully engage the workpieces.