diff --git a/CHANGELOG.md b/CHANGELOG.md
index df2fc975d..702eb8bb0 100755
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -15,6 +15,7 @@ to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 - Fixed items getting lost on Creative Disk when more than 2,147,483,647 of one type is stored
 - Fixed incorrect autocrafting keybind prompt on macOS
 - Fixed crashing the game when a network block was removed in a bad way
+- Fixed duplication bug with Constructors and Shulker Boxes
 
 ### Changed
 
diff --git a/src/main/java/com/refinedmods/refinedstorage/apiimpl/network/node/ConstructorNetworkNode.java b/src/main/java/com/refinedmods/refinedstorage/apiimpl/network/node/ConstructorNetworkNode.java
index cbd443502..36dcfbfa6 100644
--- a/src/main/java/com/refinedmods/refinedstorage/apiimpl/network/node/ConstructorNetworkNode.java
+++ b/src/main/java/com/refinedmods/refinedstorage/apiimpl/network/node/ConstructorNetworkNode.java
@@ -14,8 +14,8 @@ import com.refinedmods.refinedstorage.inventory.item.UpgradeItemHandler;
 import com.refinedmods.refinedstorage.inventory.listener.NetworkNodeFluidInventoryListener;
 import com.refinedmods.refinedstorage.inventory.listener.NetworkNodeInventoryListener;
 import com.refinedmods.refinedstorage.item.UpgradeItem;
-import com.refinedmods.refinedstorage.util.StackUtils;
 import com.refinedmods.refinedstorage.util.LevelUtils;
+import com.refinedmods.refinedstorage.util.StackUtils;
 import net.minecraft.core.BlockPos;
 import net.minecraft.core.Direction;
 import net.minecraft.core.PositionImpl;
@@ -112,6 +112,8 @@ public class ConstructorNetworkNode extends NetworkNode implements IComparable,
     private void extractAndPlaceBlock(ItemStack stack) {
         ItemStack took = network.extractItem(stack, 1, compare, Action.SIMULATE);
         if (!took.isEmpty()) {
+            // We have to copy took as the forge hook clears the item.
+            final ItemStack tookCopy = took.copy();
             BlockPlaceContext ctx = new ConstructorBlockItemUseContext(
                 level,
                 LevelUtils.getFakePlayer((ServerLevel) level, getOwner()),
@@ -122,7 +124,7 @@ public class ConstructorNetworkNode extends NetworkNode implements IComparable,
 
             InteractionResult result = ForgeHooks.onPlaceItemIntoWorld(ctx);
             if (result.consumesAction()) {
-                network.extractItem(stack, 1, Action.PERFORM);
+                network.extractItem(tookCopy, 1, Action.PERFORM);
             }
         } else if (upgrades.hasUpgrade(UpgradeItem.Type.CRAFTING)) {
             ItemStack craft = itemFilters.getStackInSlot(0);