diff --git a/src/Mod/PartDesign/InvoluteGearFeature.py b/src/Mod/PartDesign/InvoluteGearFeature.py
index a20a52a78e..dc2caee2a5 100644
--- a/src/Mod/PartDesign/InvoluteGearFeature.py
+++ b/src/Mod/PartDesign/InvoluteGearFeature.py
@@ -176,6 +176,9 @@ class _InvoluteGearTaskPanel:
         #QtCore.QObject.connect(self.form.comboBox_ExternalGear, QtCore.SIGNAL("activated(QString)"), self.externalGearChanged)
         #QtCore.QObject.connect(self.form.comboBox_ExternalGear, QtCore.SIGNAL("currentIndexChanged(int)"), self.externalGearChanged)
         QtCore.QObject.connect(self.form.comboBox_ExternalGear, QtCore.SIGNAL("currentIndexChanged(int)"), self.externalGearChanged)
+        QtCore.QObject.connect(self.form.doubleSpinBox_Addendum, QtCore.SIGNAL("valueChanged(double)"), self.addendumChanged)
+        QtCore.QObject.connect(self.form.doubleSpinBox_Dedendum, QtCore.SIGNAL("valueChanged(double)"), self.dedendumChanged)
+        QtCore.QObject.connect(self.form.doubleSpinBox_RootFillet, QtCore.SIGNAL("valueChanged(double)"), self.rootFilletChanged)
 
         self.update()
 
@@ -198,6 +201,9 @@ class _InvoluteGearTaskPanel:
         else:
             self.obj.ExternalGear = False
         #self.obj.ExternalGear       = self.form.comboBox_ExternalGear.currentIndex()
+        self.obj.AddendumCoefficient = self.form.doubleSpinBox_Addendum.value()
+        self.obj.DedendumCoefficient = self.form.doubleSpinBox_Dedendum.value()
+        self.obj.RootFilletCoefficient = self.form.doubleSpinBox_RootFillet.value()
 
 
     def transferFrom(self):
@@ -215,6 +221,9 @@ class _InvoluteGearTaskPanel:
         else:
             self.form.comboBox_ExternalGear.setCurrentIndex(1)
         #self.form.comboBox_ExternalGear.setCurrentIndex(self.obj.ExternalGear)
+        self.form.doubleSpinBox_Addendum.setValue(self.obj.AddendumCoefficient)
+        self.form.doubleSpinBox_Dedendum.setValue(self.obj.DedendumCoefficient)
+        self.form.doubleSpinBox_RootFillet.setValue(self.obj.RootFilletCoefficient)
 
     def modulesChanged(self, value):
         #print value
@@ -251,6 +260,18 @@ class _InvoluteGearTaskPanel:
         self.obj.ExternalGear = v
         self.obj.Proxy.execute(self.obj)
 
+    def addendumChanged(self, value):
+        self.obj.AddendumCoefficient = value
+        self.obj.Proxy.execute(self.obj)
+
+    def dedendumChanged(self, value):
+        self.obj.DedendumCoefficient = value
+        self.obj.Proxy.execute(self.obj)
+
+    def rootFilletChanged(self, value):
+        self.obj.RootFilletCoefficient = value
+        self.obj.Proxy.execute(self.obj)
+
     def getStandardButtons(self):
         return int(QtGui.QDialogButtonBox.Ok) | int(QtGui.QDialogButtonBox.Cancel)| int(QtGui.QDialogButtonBox.Apply)
 
diff --git a/src/Mod/PartDesign/InvoluteGearFeature.ui b/src/Mod/PartDesign/InvoluteGearFeature.ui
index 5f3eef9fd1..5af14a1797 100644
--- a/src/Mod/PartDesign/InvoluteGearFeature.ui
+++ b/src/Mod/PartDesign/InvoluteGearFeature.ui
@@ -6,8 +6,8 @@
    <rect>
     <x>0</x>
     <y>0</y>
-    <width>195</width>
-    <height>142</height>
+    <width>248</width>
+    <height>270</height>
    </rect>
   </property>
   <property name="windowTitle">
@@ -173,6 +173,66 @@
      </item>
     </widget>
    </item>
+   <item row="5" column="0">
+    <widget class="QLabel" name="label">
+     <property name="text">
+      <string>Addendum Coefficient</string>
+     </property>
+    </widget>
+   </item>
+   <item row="5" column="1">
+    <widget class="QDoubleSpinBox" name="doubleSpinBox_Addendum">
+     <property name="maximum">
+      <double>5.000000000000000</double>
+     </property>
+     <property name="singleStep">
+      <double>0.050000000000000</double>
+     </property>
+     <property name="value">
+      <double>1.000000000000000</double>
+     </property>
+    </widget>
+   </item>
+   <item row="6" column="0">
+    <widget class="QLabel" name="label_2">
+     <property name="text">
+      <string>Dedendum Coefficient</string>
+     </property>
+    </widget>
+   </item>
+   <item row="6" column="1">
+    <widget class="QDoubleSpinBox" name="doubleSpinBox_Dedendum">
+     <property name="maximum">
+      <double>5.000000000000000</double>
+     </property>
+     <property name="singleStep">
+      <double>0.050000000000000</double>
+     </property>
+     <property name="value">
+      <double>1.250000000000000</double>
+     </property>
+    </widget>
+   </item>
+   <item row="7" column="0">
+    <widget class="QLabel" name="label_3">
+     <property name="text">
+      <string>Root Fillet Coefficient</string>
+     </property>
+    </widget>
+   </item>
+   <item row="7" column="1">
+    <widget class="QDoubleSpinBox" name="doubleSpinBox_RootFillet">
+     <property name="maximum">
+      <double>2.000000000000000</double>
+     </property>
+     <property name="singleStep">
+      <double>0.020000000000000</double>
+     </property>
+     <property name="value">
+      <double>0.380000000000000</double>
+     </property>
+    </widget>
+   </item>
   </layout>
  </widget>
  <customwidgets>