diff --git a/shared/uavobjectdefinition/perfcounter.xml b/shared/uavobjectdefinition/perfcounter.xml
index cad949197..dceb82f3f 100644
--- a/shared/uavobjectdefinition/perfcounter.xml
+++ b/shared/uavobjectdefinition/perfcounter.xml
@@ -1,7 +1,7 @@
 <xml>
     <object name="PerfCounter" singleinstance="false" settings="false" category="System">
         <description>A single performance counter, used to instrument flight code</description>
-        <field name="Id" units="" type="uint32" elements="1" />
+        <field name="Id" units="hex" type="uint32" elements="1" />
         <field name="Counter" units="" type="int32" elementnames="Value, Min, Max"/>
         <access gcs="readwrite" flight="readwrite"/>
         <telemetrygcs acked="false" updatemode="manual" period="0"/>