Over the years, many! Changes to the jig include a larger top stop, more durable thumb screws, a redesigned end stop, and extending the bottom rail of the T-square by approximately 1”. We now also laser etch the numbers into the jig, where before we screen printed them over the aluminum T-Square.  In recent years, the tool has started shipping in a hard plastic case instead of a cardboard box.  Every Cabinet Hardware Jig now includes an Accessory Kit that contains Hardware Spacing Pins, Shaker Drawer Spacers, and Magnetic Bushing Covers.