The MA-WFS water flow detectors are UL and FM listed devices according to UL346 and FM1042- 2016 for indoor/outdoor use. The MA-WFS Series shall be mounted on any clear pipe span of the appropriate normal size, either a horizontal or vertical pipe. The indicators shall have a sensitivity in the range of 4-10 gallons per minute and a static pressure rating up to 450psi for 50mm thru 200mm pipes. The indicator shall respond to water flow in the specified direction after a preset time delay t hat is field adjustable. The retard structure shall be a sealed mechanical pneumatic unit with visual time delay adjustment.