This mercury collector is a polyethylene jar with screw-top lid with an attached foam pad, and an internal free-standing raised perforated disc. Remove lid with foam pad and press the pad firmly against the surface to collect mercury which has been spilled. Cells in the foam pad are opened by applied pressure so that the individual globules of Hg can enter the cells. Release pressure to close cells. Mercury is released into the jar bottom by screwing lid back onto the jar, and thereby pressing the foam pad against the perforated disc. Dimensions: 4 1/8"" O.D., 2"" high.