Home Electrical Boxes & Conduit Bodies 4-Inch Square Box Extensions

VELKOR STEEL JUNCTION BOXES & COVERS

4-Inch Square Box Extensions

Velkor 4-Inch Square Box Extensions increase the depth of a matching square box.

4-Inch Square Box Extensions Galvanized steel models are offered in 1-1/2-inch and 2-1/8-inch depths with side knockout selections. Open-frame construction extends the box above its existing rim. Two depths provide 21 or 30.3 cubic inches of capacity. TYPICAL APPLICATIONS Box extensions Raceway junctions Modern Standards for Traditional Products Verified Product verified against Velkor quality standards […]

MATERIAL

Steel

FINISH

Galvanized

Catalog No.

53151-1/2, 53151-3/4, 53151-1/2&3/4, 53171-1/2, 53171-3/4, 53171-1/2&3/4, 53171-1

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4-Inch Square Box Extensions

Galvanized steel models are offered in 1-1/2-inch and 2-1/8-inch depths with side knockout selections.

TYPICAL APPLICATIONS

Box extensions

Raceway junctions

Specifications

4-Inch Square Box Extensions

53151-1/2, 53151-3/4, 53151-1/2&3/4, 53171-1/2, 53171-3/4, 53171-1/2&3/4, 53171-1

4-Inch Square Box Extensions

Material

Steel

Finish

Galvanized

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Catalog No.	KNOCKOUTS - SIDES	Depth	Capacity
53151-1/2	12x1/2"	1-1/2"	21 cu. in.
53151-3/4	8x3/4"	1-1/2"	21 cu. in.
53151-1/2&3/4	8x1/2"+4x3/4"	1-1/2"	21 cu. in.
53171-1/2	12x1/2"	2-1/8"	30.3 cu. in.
53171-3/4	8x3/4"	2-1/8"	30.3 cu. in.
53171-1/2&3/4	8x1/2"+4x3/4"	2-1/8"	30.3 cu. in.
53171-1	8x1"	2-1/8"	30.3 cu. in.

CUT SHEET (PDF)

Outside diameter tolerances: ±.005 in (.13 mm) for trade sizes 1/2–2" (16–53 mm); ±.010 in (.25 mm) for 2-1/2" (63 mm); ±.015 in (.38 mm) for 3" (78 mm); ±.020 in (.51 mm) for 3-1/2" and 4" (91–103 mm).

No bottom knockout applies to an open extension.

Modern Standards for Traditional Products

Verified

Product verified against Velkor quality standards before it ships.

PRECISE

Precision in every detail, from engineering drawing to final delivery.

RELIABLE

Stable quality and dependable lead times you can plan a project around.

SYSTEMATIC

A structured process that keeps complex projects consistent and on track.

PARTNER

More than a supplier — we build long-term partnerships with our clients.

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Info@velkor.co

China: +86 158-6717-8588

ADDRESS

Puyang Industrial Zone, Hangzhou, Zhejiang, China

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