For use with the GRS Engraving Block. Allow for the holding of irregular shaped parts with the adjustment of your ball vise. The jaws are lined with soft vinyl rubber pads eliminating the need for excessive force to secure the work piece. The pressure required to hold an item is relatively light. For more holding versatility the small jaw can be rotated 180°. Extra rubber pads included. Fits in the top holes of any GRS Engraving Block and the Bench Mate Rotary Vise.