The universal work holder is a very versatile tool used to securely hold items while you engrave, carve, file, or set stones into them. It has 8 movable pins to hold your work and a vice that screws open and closed to hold different sized items. Made of aluminum. Position pegs in the holes of the adjustable metal jaws of this holder to secure small, flat, or odd-shaped parts for engraving, carving, filing, stone-setting and more. The jaw measures 2" in diameter when closed and opens to a maximum of 2-3/4" to accommodate a wide variety of work pieces. Its weighted base features a third-hand style ball mounting that can be adjusted to any position required by your work piece. Three pre-drilled holes allow you to mount the base securely to your bench or work surface (hardware is not included). The sturdy base (3-1/2") provides excellent hands-free support. Dimensions:4" H x 3-1/2.