diff --git a/apps/openmw/mwclass/lockpick.cpp b/apps/openmw/mwclass/lockpick.cpp
index bfbf10756..52a22d28e 100644
--- a/apps/openmw/mwclass/lockpick.cpp
+++ b/apps/openmw/mwclass/lockpick.cpp
@@ -181,4 +181,12 @@ namespace MWClass
     {
         return npcServices & ESM::NPC::Picks;
     }
+
+    int Lockpick::getItemMaxHealth (const MWWorld::Ptr& ptr) const
+    {
+        MWWorld::LiveCellRef<ESM::Lockpick> *ref =
+            ptr.get<ESM::Lockpick>();
+
+        return ref->mBase->mData.mUses;
+    }
 }
diff --git a/apps/openmw/mwclass/lockpick.hpp b/apps/openmw/mwclass/lockpick.hpp
index edd884a3e..df794debd 100644
--- a/apps/openmw/mwclass/lockpick.hpp
+++ b/apps/openmw/mwclass/lockpick.hpp
@@ -59,6 +59,9 @@ namespace MWClass
             virtual std::string getModel(const MWWorld::Ptr &ptr) const;
 
             virtual bool canSell (const MWWorld::Ptr& item, int npcServices) const;
+
+            virtual int getItemMaxHealth (const MWWorld::Ptr& ptr) const;
+            ///< Return item max health or throw an exception, if class does not have item health
     };
 }
 
diff --git a/apps/openmw/mwclass/probe.cpp b/apps/openmw/mwclass/probe.cpp
index 4ec6a8340..1c14c894d 100644
--- a/apps/openmw/mwclass/probe.cpp
+++ b/apps/openmw/mwclass/probe.cpp
@@ -180,4 +180,12 @@ namespace MWClass
     {
         return npcServices & ESM::NPC::Probes;
     }
+
+    int Probe::getItemMaxHealth (const MWWorld::Ptr& ptr) const
+    {
+        MWWorld::LiveCellRef<ESM::Probe> *ref =
+            ptr.get<ESM::Probe>();
+
+        return ref->mBase->mData.mUses;
+    }
 }
diff --git a/apps/openmw/mwclass/probe.hpp b/apps/openmw/mwclass/probe.hpp
index 75ebaa01c..70390c85c 100644
--- a/apps/openmw/mwclass/probe.hpp
+++ b/apps/openmw/mwclass/probe.hpp
@@ -59,6 +59,9 @@ namespace MWClass
             virtual std::string getModel(const MWWorld::Ptr &ptr) const;
 
             virtual bool canSell (const MWWorld::Ptr& item, int npcServices) const;
+
+            virtual int getItemMaxHealth (const MWWorld::Ptr& ptr) const;
+            ///< Return item max health or throw an exception, if class does not have item health
     };
 }
 
diff --git a/apps/openmw/mwgui/windowmanagerimp.cpp b/apps/openmw/mwgui/windowmanagerimp.cpp
index 2171beaff..36e53ca09 100644
--- a/apps/openmw/mwgui/windowmanagerimp.cpp
+++ b/apps/openmw/mwgui/windowmanagerimp.cpp
@@ -918,14 +918,16 @@ namespace MWGui
         const ESM::Enchantment* ench = MWBase::Environment::get().getWorld()->getStore().get<ESM::Enchantment>()
                 .find(MWWorld::Class::get(item).getEnchantment(item));
 
-        int chargePercent = item.getCellRef().mEnchantmentCharge / static_cast<float>(ench->mData.mCharge) * 100;
+        int chargePercent = (item.getCellRef().mEnchantmentCharge == -1) ? 100
+                : (item.getCellRef().mEnchantmentCharge / static_cast<float>(ench->mData.mCharge) * 100);
         mHud->setSelectedEnchantItem(item, chargePercent);
         mSpellWindow->setTitle(MWWorld::Class::get(item).getName(item));
     }
 
     void WindowManager::setSelectedWeapon(const MWWorld::Ptr& item)
     {
-        int durabilityPercent = item.getCellRef().mCharge / static_cast<float>(MWWorld::Class::get(item).getItemMaxHealth(item)) * 100;
+        int durabilityPercent = (item.getCellRef().mCharge == -1) ? 100
+                 : (item.getCellRef().mCharge / static_cast<float>(MWWorld::Class::get(item).getItemMaxHealth(item)) * 100);
         mHud->setSelectedWeapon(item, durabilityPercent);
         mInventoryWindow->setTitle(MWWorld::Class::get(item).getName(item));
     }