These polystyrene weighing boats have a smooth surface and rounded corners to allow easy removal of samples. These medium weigh boats have dimensions of 3.3 x 3.3 inches square x 0.75 inches high. Disposable, lightweight, with stable flat bottom and turned gripping edge. These weighing dishes are easier to manipulate than unwieldy weighing papers or heavy glass or porcelain labware. They are flexible and can be squeezed to control pour out. The thin, no-wetting polystyrene is unaffected by inorganic solutions and is ideal for handing dry or liquid samples. Polystyrene.