By default, the PenWidthLinkTo property is 1. Use the PenWidthLinkTo property to specify the width of the links between nodes, being added using the LinkTo property. The LinkToWidth property specifies the width for an linkto line. The following properties specify the style,  width and the color for links between nodes, being added using the LinkTo property:

• PenLinkTo property specifies the style of the link to be shown between nodes.
• PenWidthLinkTo property specifies the size / width of the links between nodes. 
• LinkToColor property specifies the color to show the links between nodes.

The AntiAliasing property specifies whether smoothing (antialiasing) is applied to lines or curves in the control. The ShowLinksDir property specifies whether the links shows the direction between the nodes.