diff --git a/src/main/scala/li/cil/oc/common/item/Drone.scala b/src/main/scala/li/cil/oc/common/item/Drone.scala
index 9f18c7e41..e6df19990 100644
--- a/src/main/scala/li/cil/oc/common/item/Drone.scala
+++ b/src/main/scala/li/cil/oc/common/item/Drone.scala
@@ -36,7 +36,7 @@ class Drone(val parent: Delegator) extends traits.Delegate with CustomModel {
   override protected def tooltipExtended(stack: ItemStack, tooltip: util.List[String]): Unit = {
     if (KeyBindings.showExtendedTooltips) {
       val info = new DroneData(stack)
-      for (component <- info.components if component != null) {
+      for (component <- info.components if !component.isEmpty) {
         tooltip.add("- " + component.getDisplayName)
       }
     }
diff --git a/src/main/scala/li/cil/oc/util/ResultWrapper.scala b/src/main/scala/li/cil/oc/util/ResultWrapper.scala
index b367400cf..fc844b560 100644
--- a/src/main/scala/li/cil/oc/util/ResultWrapper.scala
+++ b/src/main/scala/li/cil/oc/util/ResultWrapper.scala
@@ -1,11 +1,14 @@
 package li.cil.oc.util
 
+import net.minecraft.item.ItemStack
+
 import scala.math.ScalaNumber
 
 object ResultWrapper {
   def result(args: Any*): Array[AnyRef] = {
     def unwrap(arg: Any): AnyRef = arg match {
       case x: ScalaNumber => x.underlying
+      case x: ItemStack if x.isEmpty => null
       case x => x.asInstanceOf[AnyRef]
     }
     Array(args map unwrap: _*)