Benchtop Lab Mill. Jar Mills are available in bench or floor models and have one to six jar capacities in 1, 2 or 3 tiers. They are used for wet or dry grinding, mixing and blending of ores, chemicals, ceramics, glass, and more. Benchtop Labmill is lightweight and compact and easily adjusts to four sizes of milling jars, 16-320oz (0.5–10L).