diff --git a/Makefile b/Makefile
index 5d604026..9bf7ed44 100644
--- a/Makefile
+++ b/Makefile
@@ -2,6 +2,10 @@
 GOSSAMER_PATH=gossamer
 
 # Which board are we building for?
+# Options are:
+# - sensorwatch_pro
+# - sensorwatch_green
+# - sensorwatch_red (also known as Sensor Watch Lite)
 BOARD=sensorwatch_pro
 
 # Sensor Watch will detect the display, unless you are debugging over USB.