Format time when changing UserForm Label Caption

[USAMax]

I am trying to display the time required when it is available and all the code works except for the NumberFormat

    If Sheets("Flow").Cells(i, 5) <> "" And i > 3 Then
        UserFormFlow.Label1.Caption = _
            "Select the task to be performed." & vbCrLf & "This task will take: " & Sheets("Flow").Cells(i, 5).NumberFormat = "h:mm"   'Return the default label.
    End If
[code]

As it is the label will only say FALSE, but if I comment out, ".NumberFormat = "h:mm" it works but it is not formatted correctly.

How can I format the time from the cell for this label?