diff --git a/src/Library/Items/Item.cpp b/src/Library/Items/Item.cpp
index f8786eb..55764cf 100644
--- a/src/Library/Items/Item.cpp
+++ b/src/Library/Items/Item.cpp
@@ -10,5 +10,5 @@ bool CreatureLib::Library::Item::HasFlag(uint32_t flag) const noexcept {
 CreatureLib::Library::Item::Item(const Arbutils::CaseInsensitiveConstString& name,
                                  CreatureLib::Library::ItemCategory category,
                                  CreatureLib::Library::BattleItemCategory battleCategory, int32_t price,
-                                 std::unordered_set<uint32_t> flags)
+                                 const std::unordered_set<uint32_t>& flags)
     : _name(name), _category(category), _battleCategory(battleCategory), _price(price), _flags(flags) {}
diff --git a/src/Library/Items/Item.hpp b/src/Library/Items/Item.hpp
index 54166cc..42ae54a 100644
--- a/src/Library/Items/Item.hpp
+++ b/src/Library/Items/Item.hpp
@@ -18,7 +18,7 @@ namespace CreatureLib::Library {
 
     public:
         Item(const Arbutils::CaseInsensitiveConstString& name, ItemCategory category, BattleItemCategory battleCategory,
-             int32_t price, std::unordered_set<uint32_t> flags);
+             int32_t price, const std::unordered_set<uint32_t>& flags);
 
         inline const Arbutils::CaseInsensitiveConstString& GetName() const noexcept { return _name; }
         inline ItemCategory GetCategory() const noexcept { return _category; }