diff --git a/README.rst b/README.rst
index de200ec..1ab1fd9 100644
--- a/README.rst
+++ b/README.rst
@@ -122,6 +122,9 @@ The full usage::
           Set tmux status refresh interval in seconds. Default: 1 second
   -g <value>, --graph-lines <value>
           Set how many lines should be drawn in a graph. Default: 10
+  -m <value>, --mem-mode
+          Set the memory presentation mode, 0 for used/total, 1 for free memory and 2 for percentage.
+          Default: 0
 
 
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