For use with Jura by GRS Master Jaws (see related products below) and easily swappable without tools. Both clamps are designed for securing small odd-shaped objects for stone-setting and engraving work. The Thermo-Loc(R) Clamp (60 mm inside diameter) is used with GRS Thermo-Loc® or Jett Sett Basic™ Fixturing Compound (see related products below). It has angled sides which "lock-in" the fixturing compound. The Shellac Plate (60 mm diameter) features a textured top surface to hold shellac securely in place.