Exhibit 4.2

XXXXXXX Mechanical Technologies, Incorporated XXXXXXX INCORPORATED UNDER THE LAWS OF THE STATE OF NEVADA SEE REVERSE SIDE FOR CERTAIN DEFINITIONS CUSIP 583543 20 2 THIS CERTIFIES THAT S P E C I M E N BY is the owner of XXXXXX FULLY PAID AND NON-ASSESSABLE 9.0% SERIES A CUMULATIVE PERPETUAL PREFERRED STOCK, PAR VALUE $0.001 PER SHARE, OF MECHANICAL TECHNOLOGIES, INCORPORATED (Brooklyn, New York) transferable on the books of the Corporation by the holder hereof in person or by Attorney upon surrender of this certificate properly endorsed. This certificate is not valid until countersigned and registered by the Transfer Agent and Registrar.PREFERRED COUNTERSIGNED AND REGISTERED: IN WITNESS WHEREOF, the said Corporation has caused this certificate to be signed by facsimile signatures of its duly authorized officers. Dated: AMERICAN STOCK TRANSFER & TRUST COMPANY, LLC SECRETARY CHIEF EXECUTIVE OFFICER AUTHORIZED SIGNATURE AND REGISTRAR TRANSFER AGENT

THE BOARD OF THIS CORPORATION HAS THE AUTHORITY TO CREATE AND DETERMINE THE RELATIVE RIGHTS AND PREFERENCES OF CLASSES OR SERIES OF SHARES OF CAPITAL STOCK OTHER THAN COMMON STOCK. THIS CORPORATION WILL FURNISH TO ANY SHAREHOLDER UPON WRITTEN REQUEST SENT TO ITS PRINCIPAL EXECUTIVE OFFICES, AND WITHOUT CHARGE, A FULL STATEMENT OF THE BOARD’S AUTHORITY TO CREATE AND DETERMINE THE RELATIVE RIGHTS AND PREFERENCES OF CLASSES OR SERIES OF SHARES OF CAPITAL STOCK AS WELL AS THE DESIGNATIONS, PREFERENCES, LIMITATIONS AND RELATIVE RIGHTS OF THE SHARES OF EACH CLASS OR SERIES THEN OUTSTANDING OR AUTHORIZED TO BE ISSUED.

The following abbreviations, when used in the inscription on the face of this certificate, shall be construed as though they were written out in full according to applicable laws or regulations:

TEN COM	–	as tenants in common	UTMA	–		Custodian
					(Cust)		(Minor)
TEN ENT	–	as tenants by entireties			under Uniform Transfers to Minors
JT TEN	–	as joint tenants with right of survivorship			Act
		and not as tenants in common				(State)
Additional abbreviations may also be used though not in the above list.

For value received _____ hereby sell, assign, and transfer unto

PLEASE INSERT SOCIAL SECURITY OR OTHER
IDENTIFYING NUMBER OF ASSIGNEE

(PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS INCLUDING POSTAL ZIP CODE OF ASSIGNEE)
	Shares
of the capital stock represented by the within Certificate, and do hereby irrevocably constitute and appoint

	Attorney
to transfer the said stock on the books of the within-named Corporation with full power of substitution in the premises.

Dated _________	X
	X
	NOTICE: THE SIGNATURE TO THIS ASSIGNMENT MUST CORRESPOND WITH THE NAME AS WRITTEN UPON THE FACE OF THE CERTIFICATE IN EVERY PARTICULAR WITHOUT ALTERATION OR ENLARGEMENT OR ANY CHANGE WHATEVER.

SIGNATURE GUARANTEED

ALL GUARANTEES MUST BE MADE BY A FINANCIAL INSTITUTION (SUCH AS A BANK OR BROKER) WHICH IS A PARTICIPANT IN THE SECURITIES TRANSFER AGENTS MEDALLION PROGRAM (“STAMP”), THE NEW YORK STOCK EXCHANGE, INC. MEDALLION SIGNATURE PROGRAM (“MSP”), OR THE STOCK EXCHANGES MEDALLION PROGRAM (“SEMP”) AND MUST NOT BE DATED. GUARANTEES BY A NOTARY PUBLIC ARE NOT ACCEPTABLE.