diff --git a/devstack/settings b/devstack/settings
index 2c1bae2..c4ff3cb 100644
--- a/devstack/settings
+++ b/devstack/settings
@@ -28,4 +28,4 @@ if [ -z $COLLECTD_CONF_DIR ]; then
 fi
 
 #Custom units feature
-COLLECTD_CEILOMETER_UNITS=${COLLECTD_CUSTOMIZE_UNITS:-none}
+COLLECTD_CEILOMETER_UNITS=${COLLECTD_CUSTOM_UNITS:-none}
diff --git a/doc/source/devstackGSG.rst b/doc/source/devstackGSG.rst
index 1ced33f..ed96eac 100644
--- a/doc/source/devstackGSG.rst
+++ b/doc/source/devstackGSG.rst
@@ -71,9 +71,9 @@ To enable this feature execute the following instructions:
 * To include your new units, add the following line with your chosen units to
   your local.conf file.
 
-| COLLECTD_CEILOMETER_UNITS="<meter> <unit>"
+| COLLECTD_CUSTOM_UNITS="<meter> <unit>"
 
   If you would like to add more than one new unit include them in the same line
   and seperate each meter and its unit with a comma, as shown below.
 
-| COLLECTD_CEILOMETER_UNITS="<meter> <unit>,<meter> <unit>"
+| COLLECTD_CUSTOM_UNITS="<meter> <unit>,<meter> <unit>"
diff --git a/doc/source/usage.rst b/doc/source/usage.rst
index ef463e4..e3c1b5b 100644
--- a/doc/source/usage.rst
+++ b/doc/source/usage.rst
@@ -61,11 +61,13 @@ COLLECTD_LOG_LEVEL
     Default: info
 
 
-COLLECTD_CEILOMETER_UNITS
+COLLECTD_CUSTOM_UNITS
     (meter=unit) a comma seperated list of pairs, defining meters and their units.
     Allows existing units to be changed and new units to be set for new meters.
+    The "meter" is generally in the form of "plugin.type", where plugin and
+    plugin type are attributes of the collectd data.
 
-    Example: COLLECTD_CEILOMETER_UNITS="<meter> <unit>,<meter> <unit>"
+    Example: COLLECTD_CUSTOM_UNITS="<meter> <unit>,<meter> <unit>"
 
 
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