If Capacity = 300
    PartNumber = "118-00119-000"
Else
    Dim tempNumb as double
    tempNumb = 0.53 * Span - 148 - 20
    If Capacity=150
        tempNumb - = 2
    End If
    If Span <=2500
        tempNumb - = 505
    Else
        tempNumb - = 908
    End If
    If tempNumb > 500x
        PartNumber = "118-00119-000"
    else
        PartNumber = "118-00117-000"
    End If
End If