... Model :HFS-25 ,HFS-20,HFS-15Application Flow control used in liquid flow lines carrying water or any fluid ,not harmful to ... run of atleast 5pipe diameter on each side of the flow swhtch .AdjustmentNote :sealed adjustments are not field addjustable .To Adjust ... :1,Remove switch cover2,For higher flow rater-turn range adjusting screw clockwise3,For lower flow rater-turn range adjusting screw counter ...