Series 2540 is a standard precision-machined acrylic flow meter for liquids or gases, has direct reading air and water scales and is available in either English or Metric scales. The 2540 flow meters can be configured with a control valve on the inlet or no valve at all; fittings and valve can be specified in either brass or stainless steel; O-rings can provided with Buna-N, Viton or other optional elastomers.