diff --git a/src/engine/gameManager/ForgeManager.java b/src/engine/gameManager/ForgeManager.java
index 7d2241b8..e35d4007 100644
--- a/src/engine/gameManager/ForgeManager.java
+++ b/src/engine/gameManager/ForgeManager.java
@@ -29,7 +29,7 @@ public enum ForgeManager implements Runnable {
 
     private static final BlockingQueue<WorkOrder> forge = new DelayQueue<>();
     public static final AtomicInteger wordOrderCounter = new AtomicInteger(0);
-    public static final ConcurrentHashMap<NPC, CopyOnWriteArrayList<WorkOrder>> vendorWorkOrderLookup = new ConcurrentHashMap<>();
+    public static final ConcurrentHashMap<NPC, ConcurrentHashMap.KeySetView<WorkOrder, Boolean>> vendorWorkOrderLookup = new ConcurrentHashMap<>();
     public static final ConcurrentHashMap<Item, WorkOrder> itemWorkOrderLookup = new ConcurrentHashMap<>();
 
     @Override
diff --git a/src/engine/gameManager/NPCManager.java b/src/engine/gameManager/NPCManager.java
index 7e5acf18..59e348e0 100644
--- a/src/engine/gameManager/NPCManager.java
+++ b/src/engine/gameManager/NPCManager.java
@@ -27,7 +27,7 @@ import org.pmw.tinylog.Logger;
 
 import java.util.ArrayList;
 import java.util.HashMap;
-import java.util.List;
+import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ThreadLocalRandom;
 
 import static engine.math.FastMath.acos;
@@ -523,7 +523,7 @@ public enum NPCManager {
 
         ArrayList<Item> itemList = new ArrayList<>();
 
-        List<WorkOrder> vendorWorkOrders = ForgeManager.vendorWorkOrderLookup.get(npc);
+        ConcurrentHashMap.KeySetView<WorkOrder, Boolean> vendorWorkOrders = ForgeManager.vendorWorkOrderLookup.get(npc);
 
         for (WorkOrder workOrder : vendorWorkOrders)
             itemList.addAll(workOrder.cooking);
diff --git a/src/engine/objects/NPC.java b/src/engine/objects/NPC.java
index 1d463ae6..ddb12851 100644
--- a/src/engine/objects/NPC.java
+++ b/src/engine/objects/NPC.java
@@ -35,7 +35,6 @@ import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.concurrent.ConcurrentHashMap;
-import java.util.concurrent.CopyOnWriteArrayList;
 import java.util.concurrent.locks.ReentrantReadWriteLock;
 
 import static engine.net.client.msg.ErrorPopupMsg.sendErrorPopup;
@@ -873,7 +872,7 @@ public class NPC extends AbstractCharacter {
         // If NPC is a vendor then configure ForgeManager support
 
         if (this.contract.isTrainer() == false)
-            ForgeManager.vendorWorkOrderLookup.computeIfAbsent(this, k -> new CopyOnWriteArrayList<>());
+            ForgeManager.vendorWorkOrderLookup.computeIfAbsent(this, k -> ConcurrentHashMap.newKeySet());
 
         this.symbol = this.contract.getIconID();
         this.modTypeTable = this.contract.getNPCModTypeTable();