FORM 3
        
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

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Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940
                      
1. Name and Address of Reporting Person * Mastrangelo Joe 2. Date of Event Requiring Statement (MM/DD/YYYY)
11/16/2020 

3. Issuer Name and Ticker or Trading Symbol Eos Energy Enterprises, Inc. [EOSE]
(Last)       (First)       (Middle)
C/O EOS ENERGY ENTERPRISES, INC., 3920 PARK AVENUE
4. Relationship of Reporting Person(s) to Issuer (Check all applicable)__X__ Director                          _____ 10% Owner
___X___ Officer (give title below)        _____ Other (specify below)
Chief Executive Officer /
(Street)
EDISON, NJ 08820      
(City)             (State)             (Zip)
5. If Amendment, Date Original Filed(MM/DD/YYYY)
 

6. Individual or Joint/Group Filing(Check Applicable Line)_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Beneficially Owned
1.Title of Security
(Instr. 4)
2. Amount of Securities Beneficially Owned
(Instr. 4)
3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)
4. Nature of Indirect Beneficial Ownership
(Instr. 5)

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivate Security
(Instr. 4)
2. Date Exercisable and Expiration Date
(MM/DD/YYYY)
3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)
4. Conversion or Exercise Price of Derivative Security 5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)
6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares
Restricted Stock Units   (1)  (2) Common Stock  74531  $0  D   
Options   (3) 10/23/2030  Common Stock  1037484  $8.67  D   

Explanation of Responses:
(1)  The reporting person received restricted stock units which vest in full when the per share price of the Company's common stock quals or exceeds $12.00 at any time.
(2)  Not applicable
(3)  Beginning on 10/23/2020, so long as the reporting person remains in service, 691,691 of the shares of common stock subject to this option will vest as to 33.33% on each of the first three anniversaries of June 22, 2020; provided, that such shares shall vest in full upon the consummation of a change in control of the Company. The remaining number of shares subject to this option will vest, provided that the reporting person remains in service, on the day the Board determines that the Company has successfully closed an equity financing transaction prior to June 22, 2023. If no such transaction is consummated by June 22, 2023, any unvested portion of the option shall imeediately terminate.

Reporting Owners
Reporting Owner Name / Address
Relationships
Director 10% Owner Officer Other
Mastrangelo Joe
C/O EOS ENERGY ENTERPRISES, INC.
3920 PARK AVENUE
EDISON, NJ 08820
X
Chief Executive Officer

Signatures
/s/ Joe Mastrangelo 11/23/2020
**Signature of Reporting Person Date
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