To prevent the shank end of a connecting nail protruding from the belt parts of respective wound elements, which are formed by winding connecting nails in a vortex, from coming into contact with the belt of the other wound element by fitting a spacer between both aggregates at the time of combining the wound elements as a pair of two wound elements.

Both wound elements 3, 3 are formed by winding a connecting nail 2 held in a parallel condition at a belt element 1 in a vortex, and the shank ends of the connecting nails 2 face each other to be combined. A spacer is fitted between both the wound elements 3, 3. With a rib 16 formed on the outer tube of a cylindrical engagement part 15b inserted between the shanks of the connecting nails 2, the step part of the spacer is brought into contact with the holding plate 1a of a belt element 1 which holds the shank of the connecting nail 2. in the vicinity of openings 4, 4.