diff --git a/src/kOS/Module/kOSProcessor.cs b/src/kOS/Module/kOSProcessor.cs
index 29b272d5f..bfacd0c3f 100644
--- a/src/kOS/Module/kOSProcessor.cs
+++ b/src/kOS/Module/kOSProcessor.cs
@@ -48,6 +48,8 @@ public string Tag
         private bool firstUpdate = true;
         private bool objectsInitialized = false;
 
+        public float AdditionalMass { get; set; }
+
         /// How many times have instances of this class been constructed during this process run?
         private static int constructorCount;
 
@@ -86,14 +88,14 @@ public string Tag
         [KSPField(isPersistant = true, guiName = "CPU/Disk Upgrade Cost", guiActive = false, guiActiveEditor = true)]
         public float additionalCost = 0F;
 
-        [KSPField(isPersistant = false, guiName = "CPU/Disk Upgrade Mass", guiActive = false, guiActiveEditor = true)]
-        public float additionalMass = 0F;
+        [KSPField(isPersistant = false, guiName = "CPU/Disk Upgrade Mass", guiActive = false, guiActiveEditor = true, guiUnits = "Kg", guiFormat = "0.00")]
+        public float additionalMassGui = 0F;
 
         [KSPField(isPersistant = false, guiActive = false, guiActiveEditor = false)]
         public float diskSpaceCostFactor = 0.0244140625F; //implies approx 100funds for 4096bytes of diskSpace
 
         [KSPField(isPersistant = false, guiActive = false, guiActiveEditor = false)]
-        public float diskSpaceMassFactor = 0.0000048829F;  //implies approx 0.020kg for 4096bytes of diskSpace
+        public float diskSpaceMassFactor = 0.0000000048829F;  //implies approx 0.020kg for 4096bytes of diskSpace
 
         [KSPField(isPersistant = true, guiActive = false)]
         public int MaxPartId = 100;
@@ -249,7 +251,8 @@ private void UpdateCostAndMass()
         {
             float spaceDelta = diskSpace - baseDiskSpace;
             additionalCost = (float)System.Math.Round(spaceDelta * diskSpaceCostFactor, 0);
-            additionalMass = spaceDelta * diskSpaceMassFactor;
+            AdditionalMass = spaceDelta * diskSpaceMassFactor;
+            additionalMassGui = AdditionalMass * 1000;
         }
 
         //implement IPartMassModifier component
@@ -257,7 +260,7 @@ public float GetModuleMass(float defaultMass, ModifierStagingSituation sit)
         {
             // the 'sit' arg is irrelevant to us, but the interface requires it.
             
-            return baseModuleMass + additionalMass;
+            return baseModuleMass + AdditionalMass;
         }
         //implement IPartMassModifier component
         public ModifierChangeWhen GetModuleMassChangeWhen()