diff --git a/app/controllers/spree/admin/parts_controller.rb b/app/controllers/spree/admin/parts_controller.rb
index 100feb49..1c6ee7c9 100644
--- a/app/controllers/spree/admin/parts_controller.rb
+++ b/app/controllers/spree/admin/parts_controller.rb
@@ -20,7 +20,7 @@ def available
       @available_products = []
     else
       query = "%#{params[:q]}%"
-      @available_products = Spree::Product.search_can_be_part(query)
+      @available_products = Spree::Product.without_parts.search_can_be_part(query)
       @available_products.uniq!
     end
     respond_to do |format|
diff --git a/app/models/spree/product_decorator.rb b/app/models/spree/product_decorator.rb
index f683686d..b551c450 100644
--- a/app/models/spree/product_decorator.rb
+++ b/app/models/spree/product_decorator.rb
@@ -11,6 +11,8 @@
     .limit(30)
   }
 
+  scope :without_parts, -> { eager_load(:assemblies_parts).where("spree_assemblies_parts.assembly_id IS NULL") }
+
   validate :assembly_cannot_be_part, if: :assembly?
 
   def variants_or_master