Laser Tube / Laser Ruler

People are afraid when they swim in the sea or a lake, because it’s easy to accident. How do you figure the deep of the beach or river? Have you ever been afraid when you didn’t know how deep it is? Lasertube will make you get off from your fear by measuring the deep of the water. You can find out the deep of water by using Lasertube. When your foot don’t reach the bottom swimming, The place where the bottom are full of potholes, When your children play