diff --git a/items.lua b/items.lua
index d64acfb..ba1ea42 100644
--- a/items.lua
+++ b/items.lua
@@ -202,7 +202,7 @@ end
 
 function FILTER_MATCHING_SLOTS(target)
   return function(detail)
-    return detail ~= nil and (target == nil or (checkField(target.name, detail.name) and
+    return detail ~= nil and detail.count ~= nil and (target == nil or (checkField(target.name, detail.name) and
             checkField(target.displayName, detail.displayName) and
             checkField(target.damage, detail.damage) and
             checkField(target.enchantments, detail.enchantments)))