Set stroke width
You can specify a stroke width (thickness) ranging from 0 (zero) to 10,000 points (about 11.5 feet or 350 cm). A stroke width of 0 creates a special-case stroke that is 1 pixel wide on whichever device you output to.
To set the width of a stroke
In the Properties panel, in the Appearance category, click the Width slider.
Slide the pointer up or to the right to increase the width of the stroke, or slide it down or to the left to reduce the width. You can also click the slider and type a specific measurement.
You can increase the stroke by pressing ] (right square bracket) and decrease the stroke width by pressing [ (left square bracket).
You can also change the stroke width measurement system independently of your document measurement system. For example, you might want your rulers set to centimeters, but your strokes set to pixels. For more information, see Units and Grids options.
If you plan to export your artwork as a XAML file and do not want your stroke to show, in the Stroke gallery, select (No Stroke) to remove the stroke. Otherwise, the stroke width will be set by default to 1 pixel.