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

VELKOR STEEL JUNCTION BOXES & COVERS

4-Inch Octagon Box Extensions

Velkor Octagon Box Extensions add a 1-1/2-inch-deep galvanized steel frame to a matching octagon box.

4-Inch Octagon Box Extensions Side openings are available in 1/2-inch, 3/4-inch and mixed patterns. Three knockout patterns accommodate different side-entry requirements. 15.5-cubic-inch capacity is listed for each extension. TYPICAL APPLICATIONS Box extensions Raceway junctions Modern Standards for Traditional Products Verified Product verified against Velkor quality standards before it ships. PRECISE Precision in every detail, from […]

MATERIAL

Steel

FINISH

Galvanized

Catalog No.

55151-1/2, 55151-3/4, 55151-1/2&3/4

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4-Inch Octagon Box Extensions

Side openings are available in 1/2-inch, 3/4-inch and mixed patterns.

TYPICAL APPLICATIONS

Box extensions

Raceway junctions

Specifications

4-Inch Octagon Box Extensions

55151-1/2, 55151-3/4, 55151-1/2&3/4

4-Inch Octagon Box Extensions

Material

Steel

Finish

Galvanized

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Catalog No.	KNOCKOUTS - SIDES	Depth	Capacity
55151-1/2	4x1/2"	1-1/2"	15.5 cu. in.
55151-3/4	4x3/4"	1-1/2"	15.5 cu. in.
55151-1/2&3/4	2x1/2"+2x3/4"	1-1/2"	15.5 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).

Extension depth: 1-1/2 in.

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.

Manufacturing Center of Excellence

Contact & Inquiry

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Send us your specifications, drawings, or project requirements. We’ll help you find the right fit and get things moving. We respond within 8 hours.

Info@velkor.co

China: +86 158-6717-8588

ADDRESS

Puyang Industrial Zone, Hangzhou, Zhejiang, China

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