To Configure the Master Settings for Leaders (AutoCAD Mechanical Toolset)

At the Command prompt, enter AMOPTIONS.
In the Options dialog box, click the AM:Standards tab.
In the Standard Elements list, double-click the root node (the standard name). The Standard Settings dialog box appears.
To change the arrowhead shape, in the Arrowhead list, select the arrowhead.
To change the arrow size, in the Arrow size list, select the size.
To change the leader color, in the leader section, in the color list, select the color.
Click OK until all dialog boxes close.