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Browse 4"" Square Boxes - Extensions Parts and Components

Industrials Unlimited is an all-inclusive purchasing platform for industrial parts and components. Our inventory of more than two billion new and obsolete parts includes a broad range of products from many different part categories. One such category is 4"" Square Boxes - Extensions, which contains parts such as 4-sw-ext-spl, 4sb-mko-ehb, 4sb-mko-ext, 4sdb-mko-ext, 4se-1-2 and many others, all of which are readily available with short lead times and competitive prices. Among our competitive edges is our ability to leverage our purchasing power to secure lower costs and faster shipping times on all orders, even in AOG situations. We are able to do this due to resources such as our international supply chain network that spans the United States, Canada, and the United Kingdom. Furthermore, as an AS9120B, ISO 9001:2015, and FAA AC 00-56B accredited business, we are able to guarantee the quality and reliability of each part we sell. To see how we are revolutionizing parts procurement, submit an RFQ today for desired 4"" Square Boxes - Extensions part.

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Part No.DescriptionManufacturerSub CategoryRFQ
4-sw-ext-splSteel City 4-SW-EXT-SPL 4"" Square Extension Ring, 1-1/2"" Deep, Welded, MetallicSteel City
4sb-mko-ehbOrbit Industries 4SB-MKO-EHB 4"" Square Extension Ring, WeldedOrbit Industries
4sb-mko-extOrbit Industries 4SB-MKO-EXT 4"" Square Extension Ring, WeldedOrbit Industries
4sdb-mko-extOrbit Industries 4SDB-MKO-EXT 4"" Square Extension Ring, 2-1/8"" Deep, Welded, SteelOrbit Industries
4se-1-2Appleton 4SE-1/2 4"" Square Extension Ring, 1-1/2"" Deep, Drawn, MetallicAppleton
4se-3-4Appleton 4SE-3/4 4"" Square Extension Ring, 1-1/2"" Deep, Drawn, MetallicAppleton
4sesAppleton 4SES 4"" Square Extension Ring, 1-1/2"" Deep, Drawn, MetallicAppleton
4sesrdAppleton 4SESRD 4 In Sq Ext-thru Ring RedAppleton
4ssbesplAppleton 4SSBESPL 4"" Square Extension Ring, 1-1/2"" Deep, Welded, MetallicAppleton
53151-1-2Steel City 53151-1/2 4 INCH SQ BX EXT,STL,21CU,1/2KOIN.Steel City
53151-1-2-3-4Steel City 53151-1/2-3/4 4"" Square Extension Ring, 1-1/2"" Deep, Drawn, MetallicSteel City
53151-3-4Steel City 53151-3/4 4 INCH SQ BX EXT,STL,21CU,3/4KOIN.Steel City
531511234-20rSteel City 531511234-20R STL 531511234-20R 4 SQ 1 1/2Steel City
531511234ubSteel City 531511234UB 1/2 & 3/4 BOX EXT RING 21CUB STLSteel City
531511-23-4ub-30Steel City 531511/23/4UB-30 UNIT UPC CODE: 785991 16781Steel City
53151-subGarvin Industries 53151-SUB 4"" SQ EXTRNG,1-1/2D, FOR UTILGarvin Industries
53151-svtGarvin Industries 53151-SVT 4"" SQ EXTRNG, 1-1/2D, PLENUMGarvin Industries
53171-1Steel City 53171-1 4"" Square Extension Ring, 2-1/8"", Welded, MetallicSteel City
53171-1Garvin Industries 53171-1 4"" SQBX, 2-1/8D, DRWN,Garvin Industries
53171-subGarvin Industries 53171-SUB 4 SQ EXT RING 2-1/8 DGarvin Industries

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Americas Fastest Growing Private Company
ASA Member
NBAA Member
ISO 9001:2015 & AS9120B
Cage Code 6RE77
ITAR
eCustoms Visual Compliance
D-U-N-S Number 069876325
FAA 0056 B Accredited
ESD S20.20
AS 6081:2012
NIST 800-171 Compliance
Top Distributors 2018
Top Distributors 2020
Top Distributors 2025

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