These acrylic, block-style flow meters are clear and one piece, with built-in, brass, flow-regulating valves suitable for air or oxygen.
The scale reads in cfh. This is cubic feet per hour at standard pressure (sea level) and temperature (68°F, 20°C).
Connections are 1/8" NPT female pipe. Price includes 1/4" barbed brass inlet and outlet adapter fittings. Approximate shipping weight of a single flow meter is 1 lb. Calibrated at 0 psi.