5. This Directive shall not affect national general contract law such as the rules on the validity, formation or effect of a contract, in so far as general contract law aspects are not regulated in this Directive.
6. This Directive shall not prevent traders from offering consumers contractual arrangements which go beyond the protection provided for in this Directive.
Article 4 Level of harmonisation Member States shall not maintain or introduce, in their national law, provisions diverging from those laid down in this Directive, including more or less stringent provisions to ensure a different level of consumer protection, unless otherwise provided for in this Directive.