The F-40500GN-6 Blue White Flow Meter is made from tough machined acrylic meter body, polished to a clear finish. Direct reading permanent scale. White back reflector for easy reading. High grade Viton o-ring seals. (Optional K-series hastelloy C-276 Call For Details). Standard models #316 stainless steel, PVDF, Teflon float. (Optional K-series hastelloy C-276 Call For Details, PVDF, Teflon). Can be used in direct sunlight. Available OEM options: Private labeling, custom calibrations, custom materials. Quality material and construction that's made to last. MTR2 2-20 SCFM ACY .37 FPT