diff --git a/iocBoot/iocvxWorks/autoShutter.substitutions b/iocBoot/iocvxWorks/autoShutter.substitutions
index 87a6965528638eb14214757323227573bb9de745..59a2dc6556f836369b70767a27db25524cae414d 100644
--- a/iocBoot/iocvxWorks/autoShutter.substitutions
+++ b/iocBoot/iocvxWorks/autoShutter.substitutions
@@ -1,8 +1,14 @@
+# AutoShutter Open system databases
+# P = PV Prefix
+# S = Shutter ID (usually A)
+# BL = Beamline ID - <Sector##><ID/BM>  example: 08ID
+# T1, T2  = Countdown Timer IDs (usually 1 and 2)
+# A = AlarmClock ID (usually 1)
 file "$(STD)/stdApp/Db/autoShutter.vdb"
 {
 pattern
-{P           S       BL           T1      T2   ALM}
-{xxx:        A      "##"          1       2     1}
+{P           S       BL           T1      T2     A}
+{xxx:        A      "##ID"         1       2     1}
 }
 
 file "$(STD)/stdApp/Db/countDownTimer.vdb"