Inside Property

True if an inside border can be applied to the specified object. Read-only Boolean.

expression   Required. An expression that returns a Border object.

Example

If the current selection supports inside borders (that is, if multiple paragraphs or cells are selected), this example applies a single inside border.

Dim borderLoop As Border

For Each borderLoop In Selection.Borders
    If borderLoop.Inside = True Then _
        borderLoop.LineStyle = wdLineStyleSingle
Next borderLoop