Heyco Products, Inc. “ T h e F i r s t N a m e i n W i r e P r o t e c t i o n ” 5-15 1-800-526-4182 • 732-286-1800 (NJ) • FAX: 732-244-8843 • Web site: www.heyco.com Quick Specs Heyco® Knock-Out Seals • Plugs electrical knock-outs. • Molded in gray color to resemble galvanized steel. • Multiple trade sizes fit 1/2½ to 2½ knock-out holes. • Locks firmly in boxes up to 1/8½ thick, except for KOS2 and KOSTs which lock firmly in boxes up to 1/4½ thick. • Installs quickly with fingertip pressure (no tool required). • Economical. PANEL DIMENSIONS TRADE PART NO. DESCRIPTION PART DIMENSIONS Maximum Mounting Hole SIZE A B Thickness Diameter Silver Head Overall Gray Diameter Height in. mm. in. mm. in. mm. in. mm. .125 3,2 .875 22,2 1/2 3997 KOS 1/2 1.015 25,8 .453 11,5 .125 3,2 1.093 27,8 3/4 3998 KOS 3/4 1.218 31,0 .453 11,5 .125 3,2 1.375 34,9 1 3999 KOS 1 1.500 38,1 .453 11,5 .125 3,2 1.750 44,5 1-1/4 4000 KOS 1-1/4 1.906 48,4 .453 11,5 .125 3,2 2.000 50,8 1-1/2 4001 KOS 1-1/2 2.140 54,4 .453 11,5 .250 6,4 2.500 63,5 2 4002 KOS 2 2.730 69,3 .750 19,1 Standard color silver gray. Locking fingers in fractional increments up to the maximum panel thickness. Approximate Head Thickness: .063½ (1,6 mm). Thickness may vary. B A Material 6/6 Nylon Certifications Recognized under the Component Program of Underwriters’ Laboratories, File E51579 Certified by Canadian Standards Association, File LR8919 Flammability Rating 94V-2 Material Temperature Index 275°F (125°C)–Maximum temperature on part not to exceed 221°F (105°C) PANEL DIMENSIONS PART NO. TRADE SIZE PART DIMENSIONS Maximum Mounting Hole A B Thickness Diameter Silver Head Overall in. mm. in. mm. Gray Diameter Height .250 6,4 .875 22,2 3991 KOST 1/2 1.015 25,8 .562 14,3 .250 6,4 1.093 27,8 3992 KOST 3/4 1.218 31,0 .562 14,3 .250 6,4 1.375 34,9 3993 KOST 1 1.500 38,1 .562 14,3 .250 6,4 1.750 44,5 3994 KOST 1-1/4 1.906 48,4 .562 14,3 .250 6,4 2.000 50,8 3995 KOST 1-1/2 2.140 54,4 .579 14,7 .250 6,4 2.500 63,5 4002 KOS 2 2.730 69,3 .750 19,1 Standard color silver gray. Locking fingers in fractional increments up to the maximum panel thickness. Approximate Head Thickness: .063½ (1,6 mm). Thickness may vary. Heyco® Thick Panel Knock-Out Seals B A