Exhibit 4-SSS

---

---

THE CINCINNATI GAS & ELECTRIC COMPANY

AND

FIFTH THIRD BANK,
Trustee

---

Sixth Supplemental Indenture

Dated as of September 15, 2002

To

Indenture

Dated as of May 15, 1995

---

5.70% Debentures Due 2012

---

---

---

SIXTH SUPPLEMENTAL INDENTURE, dated as of September 15, 2002, between The Cincinnati Gas & Electric Company, a corporation duly organized and
existing under the laws of the State of Ohio (herein called the "Company"), having its principal office at 139 East Fourth Street, Cincinnati, Ohio 45202, and Fifth Third Bank, an Ohio banking
corporation, as Trustee (herein called the "Trustee"), under the Indenture dated as of May 15, 1995 between the Company and the Trustee (the "Indenture").

Recitals of the Company

The
Company has executed and delivered the Indenture to the Trustee to provide for the issuance from time to time of its unsecured debentures, notes or other evidences of indebtedness
(the "Securities"), to be issued in one or more series as provided in the Indenture.

Pursuant
to the terms of the Indenture, the Company desires to provide for the establishment of a new series of its Securities to be known as its 5.70% Debentures Due 2012 (herein called
the "Debentures"), in this Sixth Supplemental Indenture.

All
things necessary to make this Sixth Supplemental Indenture a valid agreement of the Company have been done.

Now,
Therefore, This Sixth Supplemental Indenture Witnesseth:

For
and in consideration of the premises and the purchase of the Debentures by the Holders thereof, it is mutually agreed, for the equal and proportionate benefit of all Holders of the
Debentures, as follows:

ARTICLE ONE

Terms
of the Debentures

Section 101.    There
is hereby authorized a series of Securities designated the "5.70% Debentures Due 2012". The Debentures shall mature and the principal shall be due
and payable together with all accrued and unpaid interest thereon on September 15, 2012 and shall be issued in the form of a registered Global Security without coupons, registered in the name
of Cede & Co., as nominee of The Depository Trust Company (the "Depository").

The
initial issue of the Debentures shall be limited in aggregate principal amount to $500,000,000 (except as provided in Section 301(2) of the Indenture). However, the Company
may, from time to time, without notice to or the consent of the registered holders of the Debentures then outstanding, issue additional Debentures, without limitation as to the aggregate principal
amount thereof.

Section 102.    The
provisions of Section 305 of the Indenture applicable to Global Securities shall apply to the Debentures.

Section 103.    Interest
on each of the Debentures shall be payable semiannually on March 15 and September 15 in each year (each an "Interest Payment
Date"), commencing on March 15, 2003, at the rate per annum specified in the designation of the Debentures from September 23, 2002, or from the most recent Interest Payment Date to which
interest has been paid or duly provided for. The interest so payable, and punctually paid or duly provided for, on any Interest Payment Date will be paid to the Person in whose name such Debenture (or
one or more Predecessor Securities) is registered at the close of business on the Regular Record Date for such interest, which shall be the Business Day immediately preceding such Interest Payment
Date. The amount of interest payable for any period will be computed on the basis of a 360-day year of twelve 30-day months. As used herein, "Business Day" means any day, other
than a Saturday or Sunday, or a day on which banking institutions in New York, New York are authorized or obligated by law or executive order to be closed.

1

---

Section 104.    Subject
to agreements with or the rules of the Depositary or any successor book-entry security system or similar system with respect to
Global Securities, payments of interest will be made by check mailed to the Holder of each Debenture at the address shown in the Security Register, and payments of the principal amount of each
Debenture will be made at maturity by check against presentation of the Debenture at the office or agency of the Trustee.

Section 105.    The
Debentures shall be issued in denominations of $1,000 or any integral multiple of $1,000.

Section 106.    Principal
and interest on the Debentures shall be payable in the coin or currency of the United States of America, which, at the time of payment, is
legal tender for public and private debts.

Section 107.    The
Debentures shall be subject to defeasance and covenant defeasance, at the Company's option, as provided for in Sections 1302 and 1303 of the
Indenture.

Section 108.    Subject
to the terms of Article Eleven of the Indenture, the Company shall have the right to redeem the Debentures, at any time in whole or from time to
time in part, until maturity (such redemption, a "Make-Whole Redemption"), at a Redemption Price equal to the sum of (i) the principal amount of the Debentures being redeemed plus
accrued and unpaid interest thereon to the
Redemption Date, and (ii) the Make-Whole Amount, if any, with respect to the Debentures being redeemed. For purposes of this Section 108:

"Make-Whole
Amount" means, in connection with any Make-Whole Redemption of any Debentures, the excess, if any, of (i) the sum, as determined by a Quotation
Agent, of the present value of the principal amount of such Debentures to be redeemed, together with scheduled payments of interest thereon from the Redemption Date to September 15, 2012 (not
including any portion of such payments of interest accrued as of the Redemption Date), in each case discounted to the Redemption Date on a semi-annual basis (assuming a 360-day
year consisting of twelve 30-day months) at the Adjusted Treasury Rate over (ii) 100% of the principal amount of the Debentures to be redeemed.

"Adjusted
Treasury Rate" means, with respect to any Redemption Date for a Make-Whole Redemption, the rate per annum equal to the semi-annual equivalent yield to
maturity of the Comparable Treasury Issue, calculated using a price for the Comparable Treasury Issue (expressed as a percentage of its principal amount) equal to the Comparable Treasury Price for
such Redemption Date, calculated on the third Business Day preceding the Redemption Date, plus in each case .25% (25 basis points).

"Comparable
Treasury Issue" means the United States Treasury security selected by the Quotation Agent as having a maturity comparable to the remaining term from the Redemption Date to
the Stated Maturity of the Debentures that would be utilized, at the time of selection and in accordance with customary financial practice, in pricing new issues of corporate debt securities of
comparable maturity to the remaining term of the Debentures.

"Quotation
Agent" means the Reference Treasury Dealer selected by the Trustee after consultation with the Company. "Reference Treasury Dealer" means a primary U.S. Government securities
dealer.

"Comparable
Treasury Price" means, with respect to any Redemption Date for a Make-Whole Redemption, (i) the average of the bid and asked prices for the Comparable
Treasury Issue (expressed in each case as a percentage of its principal amount) on the third Business Day preceding such Redemption Date, as set forth in the daily statistical release designated
"H.15" (or any successor release) published by the Board of Governors of the Federal Reserve System or (ii) if such release (or any successor release) is not published or does not contain such
prices on such Business Day, (A) the average of the Reference Treasury Dealer Quotations for such Redemption Date, after excluding the

2

---

highest and lowest of such Reference Treasury Dealer Quotations, or (B) if the Trustee obtains fewer than three such Reference Treasury Dealer Quotations, the average of such Quotations.

"Reference
Treasury Dealer Quotations" means, with respect to each Reference Treasury Dealer and any Redemption Date for a Make-Whole Redemption, the average, as determined
by the Trustee (after consultation with the Company), of the bid and asked prices for the Comparable Treasury Issue
(expressed in each case as a percentage of its principal amount) quoted in writing to the Trustee by such Reference Treasury Dealer at 5:00 p.m., New York City time, on the third Business Day
preceding such Redemption Date.

Notice
of any redemption by the Company will be mailed at least 30 days but not more than 60 days before any Redemption Date to each Holder of Debentures to be redeemed. If
less than all the Debentures are to be redeemed at the option of the Company, the Trustee shall select, in such manner as it shall deem fair and appropriate, the Debentures to be redeemed.

Unless
the Company defaults in payment of the Redemption Price, on and after any Redemption Date, interest will cease to accrue on the Debentures or portions thereof called for
redemption.

ARTICLE TWO

Form
of the Debentures

Section 201.    The
Debentures are to be substantially in the following form and shall include substantially the legend shown so long as the Debentures are Global
Securities:

3

---

(FORM OF FACE OF DEBENTURE)

|No. |  | $
|--- |  | -

CUSIP No.: 172070 CN 2
ISIN: US172070CN29
Common Code: 015526378

THE CINCINNATI GAS & ELECTRIC COMPANY

5.70%
DEBENTURE DUE 2012

UNLESS
THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION ("DTC"), TO ISSUER OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE, OR
PAYMENT AND SUCH CERTIFICATE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR IN SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY PAYMENT IS MADE TO
CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE, OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL
INASMUCH AS THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

THE
CINCINNATI GAS & ELECTRIC COMPANY, a corporation duly organized and existing under the laws of the State of Ohio (herein called the "Company," which term includes any
successor Person under the Indenture hereafter referred to), for value received, hereby promises to pay to CEDE & CO., or registered assigns, the principal sum
of                        and No/100
Dollars ($                        ) on September 15, 2012, and to pay interest thereon from September 23, 2002 or from
the most recent Interest Payment Date to which interest has been paid or
duly provided for, semiannually on March 15 and September 15 in each year, commencing March 15, 2003, at the rate of 5.70% per annum, until the principal hereof is paid or made
available for payment. The amount of interest payable on any Interest Payment Date shall be computed on the basis of a 360-day year of twelve 30-day months. The interest so
payable, and punctually paid or duly provided for, on any Interest Payment Date will, as provided in the Indenture, be paid to the Person in whose name this Security (or one or more Predecessor
Securities) is registered at the close of business on the Regular Record Date for such interest, which shall be the Business Day immediately preceding such Interest Payment Date. Any such interest not
so punctually paid or duly provided for will forthwith cease to be payable to the Holder on such Regular Record Date and may either be paid to the Person in whose name this Security (or one or more
Predecessor Securities) is registered at the close of business on a Special Record Date for the payment of such Defaulted Interest to be fixed by the Trustee, notice whereof shall be given to Holders
of Securities of this series not less than 10 days
prior to such Special Record Date, or be paid at any time in any other lawful manner not inconsistent with the requirements of any securities exchange on which the Securities of this series may be
listed, and upon such notice as may be required by such exchange, all as more fully provided in the Indenture.

Payment
of the principal of and interest on this Security will be made at the corporate trust office of the Trustee maintained for that purpose in the City of Cincinnati, in such coin or
currency of the United States of America as at the time of payment is legal tender for payment of public and private debts; provided, however, that at the option of the Company payment of interest may
be made by check mailed to the address of the Person entitled thereto as such address shall appear in the Security Register.

Any
payment on this Security due on any day which is not a Business Day in the City of New York need not be made on such day, but may be made on the next succeeding Business Day with the
same

4

---

force and effect as if made on the due date and no interest shall accrue for the period from and after such date, unless such payment is a payment at maturity or upon redemption, in which case
interest shall accrue thereon at the stated rate for such additional days.

As
used herein, "Business Day" means any day, other than a Saturday or Sunday, or a day on which banking institutions in New York, New York are authorized or obligated by law or
executive order to be closed.

Reference
is hereby made to the further provisions of this Security set forth on the reverse hereof, which further provisions shall for all purposes have the same effect as if set forth
at this place.

Unless
the certificate of authentication hereon has been executed by the Trustee referred to on the reverse hereof by manual signature, this Security shall not be entitled to any benefit
under the Indenture or be valid or obligatory for any purpose.

In
Witness Whereof, the Company has caused this instrument to be duly executed.

| | THE CINCINNATI GAS & ELECTRIC COMPANY
| | -------------------------------------
| | By                                   

5

---

CERTIFICATE OF AUTHENTICATION

Dated:

This
is one of the Securities of the series designated therein referred to in the within-mentioned Indenture.

| |  | FIFTH THIRD BANK,
    as Trustee |  |                     
| |  | -------------------------------- |  | --------------------
| |  | By                               |  | Authorized Signatory

(FORM OF REVERSE OF DEBENTURE)

This
Security is one of a duly authorized issue of securities of the Company (herein called the "Securities"), issued and to be issued in one or more series under an Indenture, dated as
of May 15, 1995 (herein called the "Indenture," which term shall have the meaning assigned to it in such instrument), between the Company and Fifth Third Bank, as Trustee (herein called the
"Trustee," which term includes any successor trustee under the Indenture), and reference is hereby made to the Indenture for a statement of the respective rights, limitations of rights, duties and
immunities thereunder of the Company, the Trustee and the Holders of the Securities and of the terms upon which the Securities are, and are to be, authenticated and delivered. This Security is one of
the series designated on the face hereof, which series is issuable without limitation as to the aggregate principal amount thereof.

The
Securities of this series are subject to optional redemption at any time in whole or from time to time in part, until maturity (such redemption, a "Make-Whole
Redemption"), at a Redemption Price equal to the sum of (i) the principal amount of the Securities being redeemed plus accrued and unpaid interest thereon to the Redemption Date, and
(ii) the Make-Whole Amount (as defined below), if any, with respect to the Securities being redeemed.

"Make-Whole
Amount" means, in connection with any Make-Whole Redemption of any Securities, the excess, if any, of (i) the sum, as determined by a Quotation
Agent of the present value of the principal amount of such Securities to be redeemed, together with scheduled payments of interest thereon from the Redemption Date to September 15, 2012 (not
including any portion of such payments of interest accrued as of the Redemption Date), in each case discounted to the Redemption Date on a semi-annual basis (assuming a 360-day
year consisting of twelve 30-day months) at the Adjusted Treasury Rate over (ii) 100% of the principal amount of the Securities to be redeemed.

"Adjusted
Treasury Rate" means, with respect to any Redemption Date for a Make-Whole Redemption, the rate per annum equal to the semi-annual equivalent yield to
maturity of the Comparable Treasury Issue, calculated using a price for the Comparable Treasury Issue (expressed as a percentage of its principal amount) equal to the Comparable Treasury Price for
such Redemption Date, calculated on the third Business Day preceding the Redemption Date, plus in each case .25% (25 basis points).

"Comparable
Treasury Issue" means the United States Treasury security selected by the Quotation Agent as having a maturity comparable to the remaining term from the Redemption Date to
the Stated Maturity of the Securities that would be utilized, at the time of selection and in accordance with customary financial practice, in pricing new issues of corporate debt securities of
comparable maturity to the remaining term of the Securities.

6

---

"Quotation
Agent" means the Reference Treasury Dealer selected by the Trustee after consultation with the Company. "Reference Treasury Dealer" means a primary U.S. Government securities
dealer.

"Comparable
Treasury Price" means, with respect to any Redemption Date for a Make-Whole Redemption, (i) the average of the bid and asked prices for the Comparable
Treasury Issue (expressed in each case as a percentage of its principal amount) on the third Business Day preceding such Redemption Date, as set forth in the daily statistical release designated
"H.15" (or any successor release) published by the Board of Governors of the Federal Reserve System or (ii) if such release (or any successor release) is not published or does not contain such
prices on such Business Day, (A) the average of the Reference Treasury Dealer Quotations for such Redemption Date, after excluding the highest and lowest of such Reference Treasury Dealer
Quotations, or (B) if the Trustee obtains fewer than three such Reference Treasury Dealer Quotations, the average of such Quotations.

"Reference
Treasury Dealer Quotations" means, with respect to each Reference Treasury Dealer and any Redemption Date for a Make-Whole Redemption, the average, as determined
by the Trustee (after consultation with the Company), of the bid and asked prices for the Comparable Treasury Issue (expressed in each case as a percentage of its principal amount) quoted in writing
to the Trustee by such Reference Treasury Dealer at 5:00 p.m., New York City time, on the third Business Day preceding such Redemption Date.

Notice
of any redemption by the Company will be mailed at least 30 days but not more than 60 days before any Redemption Date to each Holder of Securities to be redeemed. If
less than all the Securities are to be redeemed at the option of the Company, the Trustee shall select, in such manner as it shall deem fair and appropriate, the Securities to be redeemed.

Unless
the Company defaults in payment of the Redemption Price, on and after any Redemption Date, interest will cease to accrue on the Securities or portions thereof called for
redemption.

The
Indenture contains provisions for defeasance at any time of the entire indebtedness of this Security or certain restrictive covenants and Events of Default with respect to this
Security upon compliance with certain conditions set forth in the Indenture.

If
an Event of Default with respect to Securities of this series shall occur and be continuing, the principal of the Securities of this series may be declared due and payable in the
manner and with the effect provided in the Indenture.

The
Indenture permits, with certain exceptions as therein provided, the amendment thereof and the modification of the rights and obligations of the Company and the rights of the Holders
of the Securities of each series to be affected under the Indenture at any time by the Company and the Trustee with the consent of the Holders of a majority in principal amount of the Securities at
the time Outstanding of each series to be affected. The Indenture also contains provisions permitting the Holders of a majority in principal amount of the Securities of each series at the time
Outstanding, on behalf of the Holders of all Securities of such series, to waive compliance by the Company with certain provisions of the Indenture and certain past defaults under the Indenture and
their consequences. Any such consent or waiver by the Holder of this Security shall be conclusive and binding upon such Holder and upon all future Holders of this Security and of any Security issued
upon the registration of transfer hereof or in exchange herefor or in lieu hereof, whether or not notation of such consent or waiver is made upon this Security.

As
provided in and subject to the provisions of the Indenture, the Holder of this Security shall not have the right to institute any proceeding with respect to the Indenture or for the
appointment of a receiver or trustee or for any other remedy thereunder, unless such Holder shall have previously given the Trustee written notice of a continuing Event of Default with respect to the
Securities of this series,
the Holders of not less than 35% in principal amount of the Securities of this series at the time Outstanding shall have made written request to the Trustee to institute proceedings in respect of such

7

---

Event of Default as Trustee and offered the Trustee reasonably satisfactory indemnity, and the Trustee shall not have received from the Holders of a majority in principal amount of Securities of this
series at the time Outstanding a direction inconsistent with such request, and shall have failed to institute any such proceeding, for 60 days after receipt of such notice, request and offer of
indemnity. The foregoing shall not apply to any suit instituted by the Holder of this Security for the enforcement of any payment of principal hereof or any premium or interest hereon on or after the
respective due dates expressed herein.

No
reference herein to the Indenture and no provision of this Security or of the Indenture shall alter or impair the obligation of the Company, which is absolute and unconditional, to
pay the principal of and interest on this Security at the times, place and rate, and in the coin or currency, herein prescribed.

As
provided in the Indenture and subject to certain limitations therein set forth, the transfer of this Security is registrable in the Security Register, upon surrender of this Security
for registration of transfer at the office or agency of the Company in any place where the principal of and interest on this Security are payable, duly endorsed by, or accompanied by a written
instrument of transfer in form satisfactory to the Company and the Security Registrar duly executed by, the Holder hereof or his attorney duly authorized in writing, and thereupon one or more new
Securities of this series and of like tenor, of authorized denominations and for the same aggregate principal amount, will be issued to the designated transferee or transferees.

The
Securities of this series are issuable only in registered form without coupons in denominations of $1,000 and any integral multiple thereof. As provided in the Indenture and subject
to certain limitations therein set forth, Securities of this series are exchangeable for a like aggregate principal amount of Securities of this series and of like tenor of a different authorized
denomination, as requested by the Holder surrendering the same.

No
service charge shall be made for any such registration of transfer or exchange, but the Company may require payment of a sum sufficient to cover any tax or other governmental charge
payable in connection therewith.

Prior
to due presentment of this Security for registration of transfer, the Company, the Trustee and any agent of the Company or the Trustee may treat the Person in whose name this
Security is registered as the owner hereof for all purposes, whether or not this Security be overdue, and neither the Company, the Trustee nor any such agent shall be affected by notice to the
contrary.

All
terms used in this Security which are defined in the Indenture shall have the meanings assigned to them in the Indenture.

ARTICLE THREE

Issuance
of Debentures

Section 301.    An
initial issue of the Debentures in the aggregate principal amount of $500,000,000 may, upon execution of this Sixth Supplemental Indenture, or from
time to time hereafter, be executed by the Company and delivered to the Trustee for authentication, and the Trustee shall thereupon authenticate and deliver said Debentures upon a Company Order
without any further action by the Company. Additional Debentures may be issued by the Company pursuant to the terms of the Indenture and this Sixth Supplemental Indenture.

ARTICLE FOUR

Paying
Agent and Security Registrar

Section 401.    Fifth
Third Bank will be the Paying Agent and Security Registrar for the Debentures.

8

---

ARTICLE FIVE

Sundry
Provisions

Section 501.    Except
as otherwise expressly provided in this Sixth Supplemental Indenture or in the form of Debenture or otherwise clearly required by the context
hereof or thereof, all terms used herein or in said form of Debenture that are defined in the Indenture shall have the several meanings respectively assigned to them thereby.

Section 502.    The
Indenture, as supplemented by this Sixth Supplemental Indenture, is in all respects ratified and confirmed, and this Sixth Supplemental Indenture
shall be deemed part of the Indenture in the manner and to the extent herein and therein provided.

---

9

---

This
instrument may be executed in any number of counterparts, each of which so executed shall be deemed to be an original, but all such counterparts shall together constitute but one
and the same instrument.

In
Witness Whereof, the parties hereto have caused this Sixth Supplemental Indenture to be duly executed as of the date first above written.

| | THE CINCINNATI GAS & ELECTRIC
    COMPANY
| | -----------------------------------------
| | By                                       
| | FIFTH THIRD BANK, as Trustee             
| | By                                       

10

---

QuickLinks