Provide a rugged alternative to glass Dounce tissue grinders. Smooth pestle action requires less effort than glass tissue grinders. Unit is precision-machined of No. 316 stainless steel to exacting tolerance of 0.0005" (0.013 mm). Mortar has a flat bottom, allowing it to stand upright. Single pestle and mortar are supplied as a matched set; they are not autoclavable.Weight: 2 lb (0.9 kg)