diff --git a/src/main/scala/li/cil/oc/client/gui/DynamicGuiContainer.scala b/src/main/scala/li/cil/oc/client/gui/DynamicGuiContainer.scala
index 7e7a55611..318560a02 100644
--- a/src/main/scala/li/cil/oc/client/gui/DynamicGuiContainer.scala
+++ b/src/main/scala/li/cil/oc/client/gui/DynamicGuiContainer.scala
@@ -81,8 +81,10 @@ abstract class DynamicGuiContainer(container: Container) extends CustomGuiContai
                 mc.getTextureManager.bindTexture(component.tierIcon)
                 Gui.drawModalRectWithCustomSizedTexture(slot.xDisplayPosition, slot.yDisplayPosition, 0, 0, 16, 16, 16, 16)
               }
-              mc.getTextureManager.bindTexture(slot.getBackgroundLocation)
-              Gui.drawModalRectWithCustomSizedTexture(slot.xDisplayPosition, slot.yDisplayPosition, 0, 0, 16, 16, 16, 16)
+              if (component.hasBackground) {
+                mc.getTextureManager.bindTexture(slot.getBackgroundLocation)
+                Gui.drawModalRectWithCustomSizedTexture(slot.xDisplayPosition, slot.yDisplayPosition, 0, 0, 16, 16, 16, 16)
+              }
               GL11.glEnable(GL11.GL_DEPTH_TEST)
             case _ =>
           }
@@ -146,12 +148,6 @@ abstract class DynamicGuiContainer(container: Container) extends CustomGuiContai
     t.draw()
   }
 
-  protected override def drawGradientRect(par1: Int, par2: Int, par3: Int, par4: Int, par5: Int, par6: Int) {
-    super.drawGradientRect(par1, par2, par3, par4, par5, par6)
-    RenderState.makeItBlend()
-    GL11.glDisable(GL11.GL_LIGHTING)
-  }
-
   private def isInPlayerInventory(slot: Slot) = container match {
     case player: Player => slot.inventory == player.playerInventory
     case _ => false
diff --git a/src/main/scala/li/cil/oc/common/container/ComponentSlot.scala b/src/main/scala/li/cil/oc/common/container/ComponentSlot.scala
index c5111158e..f7847bf3f 100644
--- a/src/main/scala/li/cil/oc/common/container/ComponentSlot.scala
+++ b/src/main/scala/li/cil/oc/common/container/ComponentSlot.scala
@@ -2,6 +2,7 @@ package li.cil.oc.common.container
 
 import li.cil.oc.common
 import net.minecraft.entity.player.EntityPlayer
+import net.minecraft.inventory.IInventory
 import net.minecraft.inventory.Slot
 import net.minecraft.item.ItemStack
 import net.minecraft.util.ResourceLocation
@@ -10,7 +11,7 @@ import net.minecraftforge.fml.relauncher.SideOnly
 
 import scala.collection.convert.WrapAsScala._
 
-trait ComponentSlot extends Slot {
+abstract class ComponentSlot(inventory: IInventory, index: Int, x: Int, y: Int) extends Slot(inventory, index, x, y) {
   def container: Player
 
   def slot: String
@@ -23,6 +24,8 @@ trait ComponentSlot extends Slot {
 
   // ----------------------------------------------------------------------- //
 
+  def hasBackground = backgroundLocation != null
+
   @SideOnly(Side.CLIENT)
   override def canBeHovered = slot != common.Slot.None && tier != common.Tier.None && super.canBeHovered
 
diff --git a/src/main/scala/li/cil/oc/common/container/DynamicComponentSlot.scala b/src/main/scala/li/cil/oc/common/container/DynamicComponentSlot.scala
index 6148d03a2..c9bd38d65 100644
--- a/src/main/scala/li/cil/oc/common/container/DynamicComponentSlot.scala
+++ b/src/main/scala/li/cil/oc/common/container/DynamicComponentSlot.scala
@@ -6,9 +6,8 @@ import li.cil.oc.common.InventorySlots.InventorySlot
 import li.cil.oc.util.SideTracker
 import net.minecraft.entity.player.EntityPlayer
 import net.minecraft.inventory.IInventory
-import net.minecraft.inventory.Slot
 
-class DynamicComponentSlot(val container: Player, inventory: IInventory, index: Int, x: Int, y: Int, val info: DynamicComponentSlot => InventorySlot, val containerTierGetter: () => Int) extends Slot(inventory, index, x, y) with ComponentSlot {
+class DynamicComponentSlot(val container: Player, inventory: IInventory, index: Int, x: Int, y: Int, val info: DynamicComponentSlot => InventorySlot, val containerTierGetter: () => Int) extends ComponentSlot(inventory, index, x, y) {
   override def tier = {
     val mainTier = containerTierGetter()
     if (mainTier >= 0) info(this).tier
@@ -23,7 +22,9 @@ class DynamicComponentSlot(val container: Player, inventory: IInventory, index:
     else common.Slot.None
   }
 
-  override def getBackgroundLocation = Textures.Icons.get(slot)
+  override def hasBackground = Textures.Icons.get(slot) != null
+
+  override def getBackgroundLocation = Option(Textures.Icons.get(slot)).getOrElse(super.getBackgroundLocation)
 
   override def getSlotStackLimit =
     slot match {
diff --git a/src/main/scala/li/cil/oc/common/container/StaticComponentSlot.scala b/src/main/scala/li/cil/oc/common/container/StaticComponentSlot.scala
index fd644601c..6fd943ae4 100644
--- a/src/main/scala/li/cil/oc/common/container/StaticComponentSlot.scala
+++ b/src/main/scala/li/cil/oc/common/container/StaticComponentSlot.scala
@@ -3,9 +3,8 @@ package li.cil.oc.common.container
 import li.cil.oc.client.Textures
 import li.cil.oc.common
 import net.minecraft.inventory.IInventory
-import net.minecraft.inventory.Slot
 
-class StaticComponentSlot(val container: Player, inventory: IInventory, index: Int, x: Int, y: Int, val slot: String, val tier: Int) extends Slot(inventory, index, x, y) with ComponentSlot {
+class StaticComponentSlot(val container: Player, inventory: IInventory, index: Int, x: Int, y: Int, val slot: String, val tier: Int) extends ComponentSlot(inventory, index, x, y) {
   setBackgroundLocation(Textures.Icons.get(slot))
 
   val tierIcon = Textures.Icons.get(tier)
diff --git a/src/main/scala/li/cil/oc/common/item/Delegate.scala b/src/main/scala/li/cil/oc/common/item/Delegate.scala
index a6faf290d..63e3ab24a 100644
--- a/src/main/scala/li/cil/oc/common/item/Delegate.scala
+++ b/src/main/scala/li/cil/oc/common/item/Delegate.scala
@@ -101,11 +101,9 @@ trait Delegate {
     }
   }
 
-  def isDamageable = false
+  def showDurabilityBar(stack: ItemStack) = false
 
-  def damage(stack: ItemStack) = 0
-
-  def maxDamage(stack: ItemStack) = 0
+  def durability(stack: ItemStack) = 0.0
 
   // ----------------------------------------------------------------------- //
 
diff --git a/src/main/scala/li/cil/oc/common/item/Delegator.scala b/src/main/scala/li/cil/oc/common/item/Delegator.scala
index 033af4026..418a532c6 100644
--- a/src/main/scala/li/cil/oc/common/item/Delegator.scala
+++ b/src/main/scala/li/cil/oc/common/item/Delegator.scala
@@ -147,20 +147,14 @@ class Delegator extends Item {
 
   override def getDurabilityForDisplay(stack: ItemStack) =
     Delegator.subItem(stack) match {
-      case Some(subItem) if subItem.isDamageable => subItem.damage(stack)
+      case Some(subItem) => subItem.durability(stack)
       case _ => super.getDurabilityForDisplay(stack)
     }
 
-  override def getMaxDamage(stack: ItemStack) =
+  override def showDurabilityBar(stack: ItemStack) =
     Delegator.subItem(stack) match {
-      case Some(subItem) if subItem.isDamageable => subItem.maxDamage(stack)
-      case _ => super.getMaxDamage(stack)
-    }
-
-  override def isDamaged(stack: ItemStack) =
-    Delegator.subItem(stack) match {
-      case Some(subItem) if subItem.isDamageable => subItem.damage(stack) > 0
-      case _ => false
+      case Some(subItem) => subItem.showDurabilityBar(stack)
+      case _ => super.showDurabilityBar(stack)
     }
 
   override def onUpdate(stack: ItemStack, world: World, player: Entity, slot: Int, selected: Boolean) =
diff --git a/src/main/scala/li/cil/oc/common/item/Tablet.scala b/src/main/scala/li/cil/oc/common/item/Tablet.scala
index 4d70e5ebc..5c1fb47a3 100644
--- a/src/main/scala/li/cil/oc/common/item/Tablet.scala
+++ b/src/main/scala/li/cil/oc/common/item/Tablet.scala
@@ -49,26 +49,15 @@ class Tablet(val parent: Delegator) extends Delegate {
 
   // ----------------------------------------------------------------------- //
 
-  override def isDamageable = true
+  override def showDurabilityBar(stack: ItemStack) = true
 
-  override def damage(stack: ItemStack) = {
-    val nbt = stack.getTagCompound
-    if (nbt != null) {
+  override def durability(stack: ItemStack) = {
+    if (stack.hasTagCompound) {
       val data = new ItemUtils.TabletData()
-      data.load(nbt)
-      (data.maxEnergy - data.energy).toInt
+      data.load(stack.getTagCompound)
+      data.energy / data.maxEnergy
     }
-    else 100
-  }
-
-  override def maxDamage(stack: ItemStack) = {
-    val nbt = stack.getTagCompound
-    if (nbt != null) {
-      val data = new ItemUtils.TabletData()
-      data.load(nbt)
-      data.maxEnergy.toInt max 1
-    }
-    else 100
+    else 1.0
   }
 
   // ----------------------------------------------------------------------- //
diff --git a/src/main/scala/li/cil/oc/common/item/UpgradeBattery.scala b/src/main/scala/li/cil/oc/common/item/UpgradeBattery.scala
index 5c3ced242..b93a97344 100644
--- a/src/main/scala/li/cil/oc/common/item/UpgradeBattery.scala
+++ b/src/main/scala/li/cil/oc/common/item/UpgradeBattery.scala
@@ -10,16 +10,13 @@ class UpgradeBattery(val parent: Delegator, val tier: Int) extends Delegate with
 
   override protected def tooltipData = Seq(Settings.get.bufferCapacitorUpgrades(tier).toInt)
 
-  override def isDamageable = true
+  override def showDurabilityBar(stack: ItemStack) = true
 
-  override def damage(stack: ItemStack) = {
-    val nbt = stack.getTagCompound
-    if (nbt != null) {
-      val stored = nbt.getCompoundTag(Settings.namespace + "data").getCompoundTag("node").getDouble("buffer")
-      ((1 - stored / Settings.get.bufferCapacitorUpgrades(tier)) * 100).toInt
+  override def durability(stack: ItemStack) = {
+    if (stack.hasTagCompound) {
+      val stored = stack.getTagCompound.getCompoundTag(Settings.namespace + "data").getCompoundTag("node").getDouble("buffer")
+      1 - stored / Settings.get.bufferCapacitorUpgrades(tier)
     }
-    else 100
+    else 1.0
   }
-
-  override def maxDamage(stack: ItemStack) = 100
 }