diff --git a/kiplot/out_gerber.py b/kiplot/out_gerber.py
index 735b0442..2b8c9bca 100644
--- a/kiplot/out_gerber.py
+++ b/kiplot/out_gerber.py
@@ -17,7 +17,7 @@ class Gerber(AnyLayer):
             self.use_aux_axis_as_origin = False
             """ use the auxiliar axis as origin for coordinates """
             self.line_width = 0.1
-            """ line_width for objects without width [mm] """
+            """ [0.02,2] line_width for objects without width [mm] """
             self.subtract_mask_from_silk = False
             """ substract the solder mask from the silk screen """
             self.use_protel_extensions = False
diff --git a/kiplot/out_pdf.py b/kiplot/out_pdf.py
index 20dd7b5c..ccbe9998 100644
--- a/kiplot/out_pdf.py
+++ b/kiplot/out_pdf.py
@@ -17,7 +17,7 @@ class PDF(AnyLayer, DrillMarks):
         # Options
         with document:
             self.line_width = 0.1
-            """ for objects without width [mm] """
+            """ [0.02,2] for objects without width [mm] """
             self.mirror_plot = False
             """ plot mirrored """
             self.negative_plot = False
diff --git a/kiplot/out_ps.py b/kiplot/out_ps.py
index 230f0cd7..62d88447 100644
--- a/kiplot/out_ps.py
+++ b/kiplot/out_ps.py
@@ -16,7 +16,7 @@ class PS(AnyLayer, DrillMarks):
         # Options
         with document:
             self.line_width = 0.15
-            """ for objects without width [mm] """
+            """ [0.02,2] for objects without width [mm] """
             self.mirror_plot = False
             """ plot mirrored """
             self.negative_plot = False
diff --git a/kiplot/out_svg.py b/kiplot/out_svg.py
index e25e1772..cce915b2 100644
--- a/kiplot/out_svg.py
+++ b/kiplot/out_svg.py
@@ -17,7 +17,7 @@ class SVG(AnyLayer, DrillMarks):
         # Options
         with document:
             self.line_width = 0.25
-            """ for objects without width [mm] """
+            """ [0.02,2] for objects without width [mm] """
             self.mirror_plot = False
             """ plot mirrored """
             self.negative_plot = False