diff --git a/dump.py b/dump.py
index c583cfb..b574e46 100755
--- a/dump.py
+++ b/dump.py
@@ -35,6 +35,7 @@ LINES = [
   ('Sensor voltage', ilt.GetSensorVoltage, 'V'),
   ('Transmission', ilt.GetTransmissionPercent, '%'),
   ('Optical density', ilt.GetOpticalDensity, '%'),
+  ('100% percent setting', ilt.Get100PercentVoltage, 'V'),
 ]
 
 
diff --git a/ilt1000.py b/ilt1000.py
index 6580497..4266795 100755
--- a/ilt1000.py
+++ b/ilt1000.py
@@ -26,7 +26,6 @@ class Saturated(Error):
 
 # TODO commands:
 # eraselogdata
-# get100perc
 # getauxserialno
 # getdarkmode
 # getfactorydark
@@ -137,3 +136,7 @@ class ILT1000(object):
   def GetOpticalDensity(self):
     ret = self._SendCommand('getod')
     return float(ret) / 100
+
+  def Get100PercentVoltage(self):
+    ret = self._SendCommand('get100perc')
+    return float(ret) / 1000000