Home Electrical Boxes & Conduit Bodies 4-Inch Square Steel Boxes

VELKOR STEEL JUNCTION BOXES & COVERS

4-Inch Square Steel Boxes

Velkor 4-Inch Square Steel Boxes enclose wiring connections in a galvanized steel body.

4-Inch Square Steel Boxes The range includes 1-1/2-inch drawn boxes and 2-1/8-inch drawn or welded boxes, with different side and bottom knockout patterns. Two depths provide catalog capacities of 21 and 30.3 cubic inches. Knockout choices include single-size and combination openings. Grounding options include tapped holes or raised grounding provisions with screws. TYPICAL APPLICATIONS Wiring […]

MATERIAL

Steel

FINISH

Galvanized

Catalog No.

52151-1/2, 52151-3/4, 52151-1/2&3/4, 52151-CKO, 52151-1/2P, 52151-3/4P, 52151-1/2&3/4P, 52151-CKOP, 52171-1/2, 52171-3/4, 52171-1/2&3/4, 52171-1, 52171-3/4&1, 52171-CKO1, 52171-CKO2, 52171-1/2P, 52171-3/4P, 52171-1/2&3/4P, 52171-CKO1P, 52171W-1/2P, 52171W-3/4P, 52171W-1/2&3/4P, 52171W-1P, 52171W-3/4&1P, 52171W-MKOP

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4-Inch Square Steel Boxes

The range includes 1-1/2-inch drawn boxes and 2-1/8-inch drawn or welded boxes, with different side and bottom knockout patterns.

TYPICAL APPLICATIONS

Wiring connections

Device mounting

Specifications

1-1/2-Inch Deep Drawn Boxes

52151-1/2, 52151-3/4, 52151-1/2&3/4, 52151-CKO, 52151-1/2P, 52151-3/4P, 52151-1/2&3/4P, 52151-CKOP

2-1/8-Inch Deep Drawn and Welded Boxes

52171-1/2, 52171-3/4, 52171-1/2&3/4, 52171-1, 52171-3/4&1, 52171-CKO1, 52171-CKO2, 52171-1/2P, 52171-3/4P, 52171-1/2&3/4P, 52171-CKO1P, 52171W-1/2P, 52171W-3/4P, 52171W-1/2&3/4P, 52171W-1P, 52171W-3/4&1P, 52171W-MKOP

1-1/2-Inch Deep Drawn Boxes

Material

Steel

Finish

Galvanized

Click a row to add it to your inquiry.

Catalog No.	KNOCKOUTS - SIDES	KNOCKOUTS - BOTTOM	GROUNDING METHOD	Capacity
52151-1/2	12x1/2"	5x1/2"	Tapped Hole	21 cu. in.
52151-3/4	8x3/4"	3x1/2"+2x3/4"	Tapped Hole	21 cu. in.
52151-1/2&3/4	8x1/2"+4x3/4"	3x1/2"+2x3/4"	Tapped Hole	21 cu. in.
52151-CKO	8xCKO	3x1/2"+2x3/4"	Tapped Hole	21 cu. in.
52151-1/2P	12x1/2"	4x1/2"	Grounding bump with ground screws	21cu. in.
52151-3/4P	8x3/4"	2x1/2"+2x3/4"	Grounding bump with ground screws	21 cu. in.
52151-1/2&3/4P	8x1/2"+4x3/4"	2x1/2"+2x3/4"	Grounding bump with ground screws	21 cu. in.
52151-CKOP	8xCKO	2x1/2"+2x3/4"	Grounding bump with ground screws	21 cu. in.

CUT SHEET (PDF)

2-1/8-Inch Deep Drawn and Welded Boxes

Material

Steel

Finish

Galvanized

Click a row to add it to your inquiry.

Catalog No.	KNOCKOUTS - SIDES	KNOCKOUTS - BOTTOM	FEATURES	Capacity
52171-1/2	12x1/2"	5x1/2"	Drawn	30.3 cu. in.
52171-3/4	8x3/4"	3x1/2"+2x3/4"	Drawn	30.3 cu. in.
52171-1/2&3/4	8x1/2"+4x3/4"	3x1/2"+2x3/4"	Drawn	30.3 cu. in.
52171-1	8x1"	3x1/2"+2x3/4"	Drawn	30.3 cu. in.
52171-3/4&1	4x3/4"+4x1"	3x1/2"+2x3/4"	Drawn	30.3 cu. in.
52171-CKO1	8xCKO	3x1/2"+2x3/4"	Drawn	30.3 cu. in.
52171-CKO2	8xCKO	1x1/2"+4xCKO	Drawn	30.3 cu. in.
52171-1/2P	12x1/2"	4x1/2"	Drawn	30.3 cu. in.
52171-3/4P	8x3/4"	2x1/2"+2x3/4"	Drawn	30.3 cu. in.
52171-1/2&3/4P	8x1/2"+4x3/4"	2x1/2"+2x3/4"	Drawn	30.3 cu. in.
52171-CKO1P	8xCKO	2x1/2"+2x3/4"	Drawn	30.3 cu. in.
52171W-1/2P	12x1/2"	4x1/2"	Welded	30.3 cu. in.
52171W-3/4P	8x3/4"	2x1/2"+2x3/4"	Welded	30.3 cu. in.
52171W-1/2&3/4P	8x1/2"+4x3/4"	2x1/2"+2x3/4"	Welded	30.3 cu. in.
52171W-1P	8x1"	2x1/2"+2x3/4"	Welded	30.3 cu. in.
52171W-3/4&1P	4x3/4"+4x1"	2x1/2"+2x3/4"	Welded	30.3 cu. in.
52171W-MKOP	8x1/2"+4xMKO	2x1/2"+2xMKO	Welded	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).

CKO identifies concentric 1/2 in and 3/4 in knockouts. MKO identifies eccentric 1/2 in and 3/4 in knockouts.

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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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