    <SEC-DOCUMENT>0001047469-17-007443-index.html : 20171205
    <SEC-HEADER>0001047469-17-007443.hdr.sgml : 20171205
    <ACCEPTANCE-DATETIME>20171204213136
    ACCESSION NUMBER:		0001047469-17-007443
    CONFORMED SUBMISSION TYPE:	S-4/A
    PUBLIC DOCUMENT COUNT:		15
    FILED AS OF DATE:		20171205
    DATE AS OF CHANGE:		20171204

    FILER:

    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			LITTELFUSE INC /DE
    		CENTRAL INDEX KEY:			0000889331
    		STANDARD INDUSTRIAL CLASSIFICATION:	SWITCHGEAR & SWITCHBOARD APPARATUS [3613]
    		IRS NUMBER:				363795742
    		STATE OF INCORPORATION:			DE
    		FISCAL YEAR END:			1231

    	FILING VALUES:
    		FORM TYPE:		S-4/A
    		SEC ACT:		1933 Act
    		SEC FILE NUMBER:	333-221147
    		FILM NUMBER:		171238525

    	BUSINESS ADDRESS:
    		STREET 1:		8755 WEST HIGGINS ROAD
    		CITY:			CHICAGO
    		STATE:			IL
    		ZIP:			60631
    		BUSINESS PHONE:		773-628-1000

    	MAIL ADDRESS:
    		STREET 1:		8755 WEST HIGGINS ROAD
    		CITY:			CHICAGO
    		STATE:			IL
    		ZIP:			60631
    </SEC-HEADER>
    <DOCUMENT>
    <TYPE>S-4/A
    <SEQUENCE>1
    <FILENAME>a2233962zs-4a.htm
    <DESCRIPTION>S-4/A
    <TEXT>
    Document 1 - file: a2233962zs-4a.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-5.1
    <SEQUENCE>2
    <FILENAME>a2233962zex-5_1.htm
    <DESCRIPTION>EX-5.1
    <TEXT>
    Document 2 - file: a2233962zex-5_1.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-8.1
    <SEQUENCE>3
    <FILENAME>a2233962zex-8_1.htm
    <DESCRIPTION>EX-8.1
    <TEXT>
    Document 3 - file: a2233962zex-8_1.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-8.2
    <SEQUENCE>4
    <FILENAME>a2233962zex-8_2.htm
    <DESCRIPTION>EX-8.2
    <TEXT>
    Document 4 - file: a2233962zex-8_2.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-23.2
    <SEQUENCE>5
    <FILENAME>a2233962zex-23_2.htm
    <DESCRIPTION>EX-23.2
    <TEXT>
    Document 5 - file: a2233962zex-23_2.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-23.3
    <SEQUENCE>6
    <FILENAME>a2233962zex-23_3.htm
    <DESCRIPTION>EX-23.3
    <TEXT>
    Document 6 - file: a2233962zex-23_3.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-99.2
    <SEQUENCE>7
    <FILENAME>a2233962zex-99_2.htm
    <DESCRIPTION>EX-99.2
    <TEXT>
    Document 7 - file: a2233962zex-99_2.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-99.3
    <SEQUENCE>8
    <FILENAME>a2233962zex-99_3.htm
    <DESCRIPTION>EX-99.3
    <TEXT>
    Document 8 - file: a2233962zex-99_3.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-99.4
    <SEQUENCE>9
    <FILENAME>a2233962zex-99_4.htm
    <DESCRIPTION>EX-99.4
    <TEXT>
    Document 9 - file: a2233962zex-99_4.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>10
    <FILENAME>g211032kqi001.gif
    <DESCRIPTION>G211032KQI001.GIF
    <TEXT>
    Document 10 - file: g211032kqi001.gif

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    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>11
    <FILENAME>g211032mpi001.jpg
    <DESCRIPTION>G211032MPI001.JPG
    <TEXT>
    Document 11 - file: g211032mpi001.jpg

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    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>12
    <FILENAME>g211032mpi002.jpg
    <DESCRIPTION>G211032MPI002.JPG
    <TEXT>
    Document 12 - file: g211032mpi002.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>13
    <FILENAME>g730173.jpg
    <DESCRIPTION>G730173.JPG
    <TEXT>
    Document 13 - file: g730173.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>14
    <FILENAME>g522707.jpg
    <DESCRIPTION>G522707.JPG
    <TEXT>
    Document 14 - file: g522707.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>15
    <FILENAME>g545152.jpg
    <DESCRIPTION>G545152.JPG
    <TEXT>
    Document 15 - file: g545152.jpg

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    </SEC-DOCUMENT>