The company manufactures and exports of Durum wheat. Besides Biosphera is producing diverse models of hydrogeological whistles, groundwater Level Meter, Plopper, water and sewage samplers which might be used in diverse environmental conditions. A sounding device is really just a small tube, closed on one side, with a diameter of 24 mm. When the open bottom touches the liquid level at a fair speed, a �plopping� sound can be heard. In normal conditions the sound is clearly audible until a depth of 100 meters