ClipsShop TIDY Grommet Dies are designed for the ClipsShop TIDY Pneumatic Grommet Machine. The die is constructed of stainless steel with a patented spring loaded design that holds the grommet securely in place. These dies are self cleaning with a center hole in the bottom half of the die to allows the slugs/cuts to drop into the collection drawer below in the machine. ClipsShop TIDY Dies sets ClipsShop self-piercing grommets.