diff --git a/enderio-base/src/main/java/crazypants/enderio/base/handler/darksteel/DarkSteelRecipeManager.java b/enderio-base/src/main/java/crazypants/enderio/base/handler/darksteel/DarkSteelRecipeManager.java
index 6e0f14b8ff..92a5453ad2 100644
--- a/enderio-base/src/main/java/crazypants/enderio/base/handler/darksteel/DarkSteelRecipeManager.java
+++ b/enderio-base/src/main/java/crazypants/enderio/base/handler/darksteel/DarkSteelRecipeManager.java
@@ -6,6 +6,7 @@
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
+import java.util.stream.Collectors;
 
 import javax.annotation.Nonnull;
 
@@ -151,7 +152,11 @@ public static void addBasicTooltipEntries(@Nonnull ItemStack itemstack, EntityPl
     }
   }
 
-  public static boolean skipUpgradeTooltips = false;
+  public static void setSkipUpgradeTooltips(boolean skipUpgradeTooltips) {
+    DarkSteelRecipeManager.skipUpgradeTooltips = skipUpgradeTooltips;
+  }
+
+  private static boolean skipUpgradeTooltips = false;
 
   public static void addAdvancedTooltipEntries(@Nonnull ItemStack itemstack, EntityPlayer entityplayer, @Nonnull List<String> list, boolean flag) {
     SpecialTooltipHandler.addDetailedTooltipFromResources(list, itemstack.getUnlocalizedName());
@@ -179,13 +184,9 @@ public static void addAdvancedTooltipEntries(@Nonnull ItemStack itemstack, Entit
   }
 
   public static @Nonnull String getUpgradesAsString(@Nonnull ItemStack stack) {
-    String result = "";
-    for (IDarkSteelUpgrade upgrade : UpgradeRegistry.getUpgrades()) {
-      if (upgrade.hasUpgrade(stack)) {
-        result += "/" + upgrade.getUnlocalizedName();
-      }
-    }
-    return result.isEmpty() ? "" : NullHelper.first(result.substring(1), "");
+    return NullHelper.first(UpgradeRegistry.getUpgrades().stream().filter(upgrade -> upgrade.hasUpgrade(stack))
+        .map(upgrade -> "" + UpgradeRegistry.getId(upgrade)).collect(Collectors.joining("/")), "");
+    // Note: Using the numeric ID here to keep the string short and save memory
   }
 
   public static NNList<ItemStack> getRecipes(@Nonnull Set<UpgradePath> list, @Nonnull NNList<ItemStack> input) {
diff --git a/enderio-base/src/main/java/crazypants/enderio/base/handler/darksteel/UpgradeRegistry.java b/enderio-base/src/main/java/crazypants/enderio/base/handler/darksteel/UpgradeRegistry.java
index adec797f9f..7dbc47af76 100644
--- a/enderio-base/src/main/java/crazypants/enderio/base/handler/darksteel/UpgradeRegistry.java
+++ b/enderio-base/src/main/java/crazypants/enderio/base/handler/darksteel/UpgradeRegistry.java
@@ -16,6 +16,7 @@
 import net.minecraftforge.fml.common.Mod.EventBusSubscriber;
 import net.minecraftforge.fml.common.eventhandler.EventPriority;
 import net.minecraftforge.fml.common.eventhandler.SubscribeEvent;
+import net.minecraftforge.registries.ForgeRegistry;
 import net.minecraftforge.registries.IForgeRegistry;
 import net.minecraftforge.registries.IForgeRegistry.AddCallback;
 import net.minecraftforge.registries.IForgeRegistry.ClearCallback;
@@ -59,4 +60,8 @@ public static void registerRegistry(@Nonnull RegistryEvent.NewRegistry event) {
     return REGISTRY.getValue(id);
   }
 
+  public static int getId(IDarkSteelUpgrade upgrade) {
+    return ((ForgeRegistry<IDarkSteelUpgrade>) REGISTRY).getID(upgrade);
+  }
+
 }
diff --git a/enderio-base/src/main/java/crazypants/enderio/base/integration/jei/DescriptionRecipeCategory.java b/enderio-base/src/main/java/crazypants/enderio/base/integration/jei/DescriptionRecipeCategory.java
index da9a1d2436..0d643054e7 100644
--- a/enderio-base/src/main/java/crazypants/enderio/base/integration/jei/DescriptionRecipeCategory.java
+++ b/enderio-base/src/main/java/crazypants/enderio/base/integration/jei/DescriptionRecipeCategory.java
@@ -63,10 +63,10 @@ public void apply(@Nonnull Item item) {
         ItemStack itemStack = new ItemStack(item);
         NNList<String> allTooltips;
         try {
-          DarkSteelRecipeManager.skipUpgradeTooltips = true;
+          DarkSteelRecipeManager.setSkipUpgradeTooltips(true);
           allTooltips = SpecialTooltipHandler.getAllTooltips(itemStack);
         } finally {
-          DarkSteelRecipeManager.skipUpgradeTooltips = false;
+          DarkSteelRecipeManager.setSkipUpgradeTooltips(false);
         }
 
         NNList<UpgradePath> list = DarkSteelRecipeManager.getAllRecipes(new NNList<>(itemStack));