D. K. Instruments pvt. Ltd. An iso 9001:2000 certified company manufactures a wide range of level, flow and pressure instruments. Submersible level probes are special instruments which are hydrostatic continuous level probes that have the same features as the pressure sensors with one main difference. They are submersible. Hydrostatic level probes are specifically designed for depth/level measurements in groundwater, deep wells, water towers, rivers, sewage treatment plants and other similar applications. The hydrostatic level probes are fully encapsulated and are Housed in a weatherproof cylindrical enclosure.