Page 1

X FORM 10 - K ANNUAL REPORT PURSUANT TO SECTION 13 OR 15 ( d ) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31 , 2020 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington , D.C. 20549 Title of Each Class None TRANSITION REPORT PURSUANT TO SECTION 13 OR 15 ( d ) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from Commission file number 001-35944 PSI POWER SOLUTIONS INTERNATIONAL to Delaware ( State or Other Jurisdiction of Incorporation or Organization ) 201 Mittel Drive , Wood Dale , IL ( Address of Principal Executive Offices ) or POWER SOLUTIONS INTERNATIONAL , INC . ( Exact Name of Registrant as Specified in its Charter ) Large accelerated filer Non - accelerated filer X ( 630 ) 350-9400 ( Registrant's Telephone Number , Including Area Code ) Securities Registered Pursuant to Section 12 ( b ) of the Act : Trading Symbol ( s ) Securities Registered Pursuant to Section 12 ( g ) of the Act : Common Stock , par value $ 0.001 per share 33-0963637 ( I.R.S. Employer Identification No. ) Indicate by check mark if the registrant is a well - known seasoned issuer , as defined in Rule 405 of the Securities Act . YES ¨ NO X Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 and Section 15 ( d ) of the Act . YES NO X 60191 ( Zip Code ) Name of Each Exchange on Which Registered Indicate by check mark whether the registrant ( 1 ) has filed all reports required to be filed by Section 13 or 15 ( d ) of the Securities Exchange Act of 1934 during the preceding 12 months ( or for such shorter period that the registrant was required to file such reports ) , and ( 2 ) has been subject to such filing requirements for the past 90 days . YES X NO Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S - T during the preceding 12 months ( or for such shorter period that the registrant was required to submit such files ) . YES X NO Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S - K is not contained herein , and will not be contained , to the best of the registrant's knowledge , in definitive proxy or information statements incorporated by reference in Part III of this Form 10 - K or any amendment to this Form 10 - K . Indicate by check mark whether the registrant is a large accelerated filer , an accelerated filer , a non - accelerated filer , a smaller reporting company , or an emerging growth company . See the definitions of " large accelerated filer , ” “ accelerated filer , ” “ smaller reporting company ” and “ emerging growth company ” in Rule 12b - 2 of the Exchange Act : 1 Accelerated filer Smaller reporting company Emerging growth company X If an emerging growth company , indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13 ( a ) of the Exchange Act . Indicate by check mark whether the registrant is a shell company ( as defined in Rule 12b - 2 of the Exchange Act ) . YES NO X