Cones (06340-02) are made of clear styrene-acrylonitrile cone features a leakproof plug for use with a heavy-gauge steel support rack (06340-20). Rack holds up to three cones and measures 17-1/2"L x 5-1/2"W x 16"H. Order racks and cones separately. Use settling cones and rack to determine settleable materials in water and wastewater samples Cones are externally graduated in mL from the bottom upward