protected function getIntervalItems()
	{
		$manager = \Aimeos\MShop::create( $this->getContext(), 'attribute' );

		$search = $manager->createSearch();
		$expr = [
			$search->compare( '==', 'attribute.type', 'interval' ),
			$search->compare( '==', 'attribute.domain', 'product' ),
		];
		$search->setConditions( $search->combine( '&&', $expr ) );
		$search->setSortations( [$search->sort( '+', 'attribute.code' )] );

		return $manager->searchItems( $search );
	}