Any notice required or permitted by this Agreement shall be in writing and shall be deemed sufficient upon delivery, when delivered personally or by overnight courier or sent by email or fax (upon customary confirmation of receipt), or 48 hours after being deposited in the U.S. mail as certified or registered mail with postage prepaid, addressed to the Party to be notified at such Party’s address or fax number as set forth in the Purchase Agreement or the Schedules hereto, or as subsequently modified by written notice.