A multi-tier winding coil 1 of a welding wire in a hollow cylindrical configuration having a beginning wire end which is located in the innermost tier and at one of cylinder end faces, a combination of such coil with a shipment packaging box 21, and a combination of the coil 1 and a wire feed adapter 5 which is used to mount the coil on a welding machine are disclosed. The coil 1 includes bundling wires 3a-3d. The beginning wire end of the coil is bent to extend in a radial direction of the coil loop, and is then bent in a direction to extend parallel to the center axis of the coil, thus defining an L-configuration 1sr+1sa. A wire feed adapter 5 includes a barrel 5b formed with notches 5br-5br4 and 5ar-5a4 for receiving beginning ends 1s.