The Jack Belt® works with a track in one side of the leather which the buckle catches onto with a spring tooth, this is on the underside of the leather giving a clean, seamless look.
It means the Jack Belt® cannot be reversible due to this track.
The advantage though is you can have one buckle for many leathers or many buckles for one leather.
Another advantage is there are no holes wearing on the leather tearing and stretching, reroding the leather and the clean cut appearance.
Yet another advantage is you aren't adjusting your belt by inches, but by millimetres and so discretly you can adjust the belt and take the strain off your belly after a large meal.