Plastic container with screw top and slotted well. Includes a sponge, which fits into well. Place your extra clay below, dampen sponge and close tightly to keep your metal clay moist. Measure 2 3/4 inches in diameter by 1 3/4 deep. Works fantastic for underglazes as well.
For underglazes you the sponge like a ink pad and saturate it with glaze. Spritz with water before dipping stamp into sponge.