This office lease form is a tenant's letter of credit to the owner in the place of a security deposit. The letter of credit maintains effect at all times during the term of the lease following delivery thereof. A clean, unconditional and irrevocable letter of credit shall have an expiration date no earlier than the first anniversary of the date of issuance and shall provide that it shall be automatically renewed from year to year unless terminated by a bank by notice to the owner. The final expiration date of the letter of credit (including any renewals) shall be no earlier than sixty days after expiration date of lease.