Heyco® Knock-Out Seals and Thick Panel Knock-Out Seals

Mounting Hole Diameter Range: 1/2″ to 2″ Electrical Knock-Outs (.875″ to 2.500″ nominal)

Specifications

Part number and specification

MOUNTING HOLE DIAMETER		TRADE SIZE	PART NO.	DESCRIPTION	PART DIMENSIONS
MOUNTING HOLE DIAMETER			Silver Gray		A Head Diameter		B Overall Height
in.	mm.		Silver Gray		in.	mm.	in.	mm.
Multiple Locking Steps for Panel Thickness up to .125" (3,2 mm)
.875	22,2	1/2	3997	KOS 1/2	1.02	25,8	.45	11,5
1.093	27,8	3/4	3998	KOS 3/4	1.22	31,0
1.375	34,9	1	3999	KOS 1	1.50	38,1
1.750	44,5	1-1/4	4000	KOS 1-1/4	1.91	48,4	.47	12,0
2.000	50,8	1-1/2	4001	KOS 1-1/2	2.16	54,9	.45	11,5
Multiple Locking Steps for Panel Thickness up to .250" (6,4 mm)
.875	22,2	1/2	3991	KOST 1/2	1.02	25,8	.56	14,3
1.093	27,8	3/4	3992	KOST 3/4	1.22	31,0
1.375	34,9	1	3993	KOST 1	1.50	38,1
1.750	44,5	1-1/4	3994	KOST 1-1/4	1.91	48,4
2.000	50,8	1-1/2	3995	KOST 1-1/2	2.16	54,9	.58	14,7
2.500	63,5	2	4002	KOS 2	2.73	69,3	.75	19,1

Standard color silver gray.

Plug electrical knock-outs.
Molded in silver gray color to resemble galvanized steel.
Install quickly with fingertip pressure (no tool required).
Economical.
Multiple trade sizes fit 1/2″ to 2″ knock-out holes.
Lock firmly in boxes up to 1/8″ thick, except for Part Number 4002 (KOS 2) and Thick Panel Knock-Out Seals (KOST’s), which lock firmly in boxes up to 1/4″ thick.
Locking fingers in fractional increments up to the maximum panel thickness.
Approximate Head Thickness: .062″ (1,6 mm). Thickness may vary.
To adapt a Knock-Out to accept a Heyco Strain Relief, see Heyco Knock-Out Adapters.

Material		Nylon 6/6
Certifications		Recognized under the Component Program of Underwriters’ Laboratories File E51579
Certifications		Certified by the Canadian Standards Association File 8919
Flammability Rating		94V-2
Temperature Range		-40°F (-40°C) to 221°F (105°C)

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