diff --git a/README.md b/README.md
index 2c59bf2..3521267 100644
--- a/README.md
+++ b/README.md
@@ -48,7 +48,7 @@ switchers.  Each available algorithm is described with the following values:
 bin: command line to launch miner.  {HOST}, {PORT}, {USERNAME}, and
   {PASSWORD} will be filled in by the switcher.
 
-power_limit: power limit for GPU(s)
+power_limit: power limit for GPU(s), W
 
 gpu_oc: GPU overclock, MHz (or negative for underclock; 0 for stock speed)