a first track and a second track, each track comprising two fastener rows matable with each other;

a central slider coupled to and slideable along both the first and second tracks, said central slider having a first end and a second end;

a plurality of paths in said central slider, said paths through which said tracks travel when said slider slides along said tracks, the paths thereby causing the rows of the first and second tracks to interchange; and

an angled opening at each end of the central slider, said openings being shaped to facilitate rotation of the tracks within the central slider so that the rotation of the tracks within said central slider begins while the fastener rows are being disconnected from each other in preparation for said interchange.