Features

• I can see a flow at first sight
  It is a rheoscope confirming fluid flow by the movement of transparent balls (or afloat) in the jurisdiction. I cannot confirm the flow quantity.
• With protective cover
  By a metal protective cover, I reduce the possibility of the damage by shocks from the outside.
• The installation direction does not matter. Because I use a spring inside, the posture when I attach it looks up and looks down and can perform sideways-facing freely.