Flow Indicators

OPW Engineered Systems has been manufacturing sight flow indicators for more than 60 years. Our experience has led to many innovations in design and manufacturing, making VISI-FLO® the most thoroughly engineered sight flow indicator on the market. VISI-FLOs are available in three series: the standard 1400 Series, 1500 High-Pressure / High-Temperature Series and the 1600 OEM Series.

Standard Features

  • Exclusive 3-Year “No-Leak” Guarantee – VISI-FLO’s innovative radial seal creates a constant and uninterrupted sealing force between the body and outside diameter of the glass lens. This sealing method provides a longer-lasting and better seal than conventional flat seals.

  • Maintenance-Free Design – VISI-FLO’s unique bolt-on-body design requires no special maintenance or torquing sequence to prevent leaks. This results in a safer, more reliable sight flow indicator than those units using tie rods to fasten lens and seal to body.

  • Dimensionally Interchangeable – “FJP” Flanged VISI-FLOs feature end-to-end dimensions that match Jacoby-Tarbox and Penberthy and other manufacturers’ units. “FJP” units are available in 3/4", 2", 3" and 4".

  • Shipment Within 48-Hours on Most Items

  • Rated for Full-Vacuum Service

Four Indicator Styles:

  • Propeller – The best way to show flow of opaque liquids. Ideal for observation at a distance. Flow from right to left is standard. Specify if left-to-right flow is needed. Not recommended for flow rates more than 100 GPM.

  • Bi-Directional Flapper – This indicator points in either direction to show you at a glance which way the liquid is flowing.

  • Bi-Directional Plain – When the color and clarity of your liquid are of prime importance.

  • Drip Tube – Ideal for gravity, extremely low or intermittent flow. Keeps product from dripping on the glass. Ensures constant see-through for vertical lines.