Dwyer, HFS-2-02, Series HF In-Line Flow Monitor, 304 SS, 1/2' female NPT, 0.2-2 GPM Water±2.5% Accuracy, Unrestricted MountingLow Cost, Series HF In-Line Flow Monitors have a design based on a floating sharp-edged orifice disk and variable area flow measurement to yield accuracy of ±2.5% over center one-third of scale. This unique design allows accurate performance with fluid viscosities up to 500 SSU. All internal wetted parts are contained inside a sealed metal tubular casing assuring a virtually maintenance-free unit. Flowing media forces linear motion of a spring loaded, sharp edge orifice disk and ring shaped transfer magnet which both ride on a tapered center shaft. The transfer magnet drives a clearly visible magnet follower located outside the flow tube, protected under the clear polycarbonate tube. A ring on the magnet follower indicates flow rate on the direct reading scale. Rubber bumpers are provided for external impact resistance.Designed for single-direction flow, Series HF Monitors are recommended for use with system filtration of at least 74 microns or a 200 mesh screen. Some applications may also require magnetic filtration. These flowmeters do not require inlet or outlet straight plumbing and can be mounted horizontally, vertically, or inverted.Product ApplicationsUsed to set flow rates, fluid motor and cylinder speeds.Check pump high pressure performance, pressure relief valve settings, fluid handling systems in agricultural, construction or industrial machinery, power tools and equipment.Monitor petrochemical operations with brass or stainless steel models.Industrial pneumatic systems air flow can be monitored with the HFA models which are calibrated at 100 psig inlet pressure.