level measurement instrument for measuring, detecting and indicating fluid liquid, viscous liquid, slurry and sludge levels, and solids levels in open or closed vessels such as tanks, troughs or other industrial containers, and for measuring, detecting and indicating liquid levels in open bodies of water such as rivers and pools

level measurement instrument for measuring, detecting and indicating fluid liquid, viscous liquid, slurry and sludge levels, and solids levels in open or closed vessels such as tanks, troughs or other industrial containers, and for mesuring, detecting and indicating liquid levels in open bodies of water such as rivers and pools