The LineJoin property returns or specifies the type of join for lines that intersect in an outline. The LineJoin property returns a value of cdrOutlineLineJoin.
Examples:
The following VBA example assigns round line caps and round joins to the outline of the selected shape.
Sub Test()
ActiveShape.Outline.LineCaps = cdrOutlineRoundLineCaps
ActiveShape.Outline.LineJoin = cdrOutlineRoundLineJoin
End Sub