UNITED STATES                                  
                       SECURITIES AND EXCHANGE COMMISSION                       
                                   Washington                                   
                                  ,D.C. 20549                                   
                                                                                
                                                                                
                                 SCHEDULE 13G*                                  
                                 (Rule 13d-102)                                 
                                                                                
             INFORMATION TO BE INCLUDED IN STATEMENTS FILEDPURSUANT             
                                       TO                                       
          (s) 240.13d-1(b), (c), AND (d) AND AMENDMENTS THERETO FILED           
                                   PURSUANTTO                                   
                                 (s) 240.13d-2                                  
                               (Amendment No. 2)*                               
                                                                                
                                                                                

             Standard Motor Products Inc              
                   (Name of Issuer)                   
                                                      
                     Common Stock                     
            (Title of Class of Securities)            
                                                      
                      853666105                       
                    (CUSIP Number)                    
                                                      
                  December 31, 2023                   
(Date of Event Which Requires Filing of the Statement)


Check the appropriate box to designate the rulepursuant to which this Schedule 
is filed:


x Rule 13d-1(b)
o Rule 13d-1(c)
o Rule 13d-1(d)

*The remainder of this cover page shall be filledout for a reporting person's 
initial filing on this form with respect to the subject class of securities, 
and for any subsequentamendment containing information which would alter the 
disclosures provided in a prior cover page.

The information required in the remainder of thiscover page shall not be 
deemed to be "filed" for the purpose of Section 18 of the Securities Exchange 
Act of 1934 ("Act")or otherwise subject to the liabilities of that section of 
the Act but shall be subject to all other provisions of the Act (however, 
seethe Notes).






CUSIP:    Page 2
853666105       




                                                                      
 1. NAME OF REPORTING PERSONS                                         
                                                                      
    William Blair Investment Management, LLC                          
                                                                      
 2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP                  
    (see instructions)                                                
                                                                   (a)
                                                                     o
                                                                   (b)
                                                                     o
                                                                      
                                                                      
 3. SEC USE ONLY                                                      
                                                                      
                                                                      
 4. CITIZENSHIP OR PLACE OF ORGANIZATION                              
                                                                      
    Delaware                                                          
         NUMBER OF                                                    
           SHARES                     5.          SOLE VOTING POWER   
        BENEFICIALLY                                                  
          OWNED BY                                621,487             
            EACH                                                      
         REPORTING                                                    
           PERSON                                                     
            WITH                                                      
                            
 6. SHARED VOTING POWER     
                            
    0                       
                            
 7. SOLE DISPOSITIVE POWER  
                            
    1,034,912               
                            
 8. SHARED DISPOSITIVE POWER
                            
    0                       
                                                                      
 9. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON      
                                                                      
    1,034,912                                                         
                                                                      
10. CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES  
    (SEE INSTRUCTIONS)                                                
                                                                     o
                                                                      
11. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)                 
                                                                      
    4.8%                                                              
                                                                      
12. TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)                       
                                                                      
    IA                                                                
                                                                      







CUSIP:    Page 3
853666105       




Item 1(a). Name of Issuer:                                                                  
           Standard Motor Products Inc                                                      
Item 1(b). Address of Issuer's Principal Executive Offices:                                 
           37-18 Northern Blvd, Long Island City, NY 11101                                  
                                                                                            
Item 2(a). Name of Person Filing:                                                           
           William Blair Investment Management, LLC                                         
Item 2(b). Address of Principal Business Office or, if none, Residence:                     
           150 North Riverside Plaza, Chicago, IL 60606                                     
Item 2(c). Citizenship:                                                                     
           Delaware                                                                         
Item 2(d). Title of Class of Securities:                                                    
           Common Stock                                                                     
Item 2(e). CUSIP Number:                                                                    
           853666105                                                                        
   Item 3.                       If this statement is filed pursuant to (s)(s) 240.13d-1(b),
                               or 240.13d-2(b) or (c), check whether the person filing is a:
           (a) o Broker or dealer registered under                                          
                 Section 15 of the Act (15 U.S.C. 78o);                                     
           (b) o Bank as defined in Section 3(a)(6)                                         
                 of the Act (15 U.S.C. 78c);                                                
           (c) o Insurance company as defined in Section                                    
                 3(a)(19) of the Act (15 U.S.C. 78c);                                       
           (d) o Investment company registered under Section 8 of the                       
                 Investment Company Act of 1940 (15 U.S.C. 80a-8);                          
           (e) x An investment adviser in accordance                                        
                 with (s) 240.13d-1(b)(1)(ii)(E);                                           
           (f) o An employee benefit plan or endowment fund in                              
                 accordance with (s) 240.13d-1(b)(1)(ii)(F);                                
           (g) o A parent holding company or control person in                              
                 accordance with (s) 240.13d-1(b)(1)(ii)(G);                                
           (h) o A savings association as defined in Section 3(b) of                        
                 the Federal Deposit Insurance Act (12 U.S.C. 1813);                        
           (i) o A church plan that is excluded from the definition of an investment company
                 under Section 3(c)(14) of the Investment Company Act (15 U.S.C. 80a-3);    
           (j) o A non-U.S. institution in accordance                                       
                 with (s) 240.13d-1(b)(1)(ii)(J);                                           
           (k) o Group, in accordance with                                                  
                 (s) 240.13d-1(b)(1)(ii)(K).                                                


If filing as a non-U.S. institution in accordance with (s)240.13d-1(b)(1)(ii)(J)
, please specify the type of institution: ____________.






CUSIP:    Page 4
853666105       




 Item 4.                                                                                                           Ownership:
         Provide the following information                                                                                   
         regarding the aggregate number and                                                                                  
         percentage of the class of securities                                                                               
         of the issuer identified in Item 1.                                                                                 
                          (a)                                                            Amount beneficially owned: 1,034,912
                          (b)                                                                          Percent of class: 4.8%
                          (c)                                                    Number of shares as to which the person has:
                                                                 (i)                                 Sole power to vote or to
                                                                                                     direct the vote: 621,487
                                                                 (ii)                                 Shared power to vote or
                                                                                                        to direct the vote: 0
                                                                (iii)                                   Sole power to dispose
                                                                                                                 or to direct
                                                                                                the disposition of: 1,034,912
                                                                 (iv)                           Shared power to dispose or to
                                                                                                 direct the disposition of: 0
 Item 5.                                                                        Ownership of Five Percent or Less of a Class:
         If this statement is being filed to report the fact                                                                 
         that as of the date hereof the reporting person has                                                                 
         ceased to be the beneficial owner of more than 5 percent                                                            
         of the class of securities, check the following.                                                                    
         x                                                                                                                   
Item 6.  Ownership of More Than Five Percent on Behalf of Another Person:                                                    
         N/A                                                                                                                 
Item 7.  Identification and Classification of the Subsidiary Which Acquired                                                  
         the Security Being Reported on By the Parent Holding Company:                                                       
         N/A                                                                                                                 
Item 8.  Identification and Classification of Members of the Group:                                                          
         N/A                                                                                                                 
Item 9.  Notice of Dissolution of Group:                                                                                     
         N/A                                                                                                                 
Item 10. Certifications:                                                                                                     
              By signing below, I certify that, to the best of my knowledge and belief, the securities referred to above were
              acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose
           of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired
                    and are not held in connection with or as a participant in any transaction having that purpose or effect.








CUSIP:    Page 5
853666105       



                                   SIGNATURE                                    
                                                                                
After reasonable inquiry and tothe best of my knowledge and belief, I certify 
that the information set forth in this statement is true, complete and correct.




 Date:  February 12, 2024                            
                                                     
 By:    /s/ Stephanie Braming                        
                                                     
 Name:  Stephanie Braming                            
                                                     
 Title: Partner, Global Head of Investment Management
                                                     


The original statement shall be signed by each person on whose behalfthe 
statement is filed or his authorized representative. If the statement is 
signed on behalf of a person by his authorized representativeother than an 
executive officer or general partner of the filing person, evidence of the 
representative's authority to sign on behalfof such person shall be filed with 
the statement,
Provided, however
, that a power of attorney for this purpose which is alreadyon file with the 
Commission may be incorporated by reference. The name and any title of each 
person who signs the statement shall be typedor printed beneath his signature.


  Attention: Intentional misstatementsor omissions of fact constitute Federal   
                              criminal violations                               
                                       (                                        
                                      see                                       
                                18 U.S.C. 1001).