The fields with the red border are required.
ASTM F1083 Sch 40 Steel Pipe and ASTM F1043 Group IA
Wind Speed MPH
    Mph   km/h  
    Fence Height - Feet                
    Ft   m  
    Line Post O.D. -- Inches                
    in.   mm  
    Description     << If value to the left is zero, Height / Line Post combination is invalid
    Wind Exposure Category                
    Icing Effect                
Line Post Spacing  >>>>>>>>
Line Post Spacing  50K  >>>>
Maximum Post Spacing -- Center-to-Center --7 Feet, 9 inches 
or 9 Feet, 9 inches depending on panel