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Varglas ES-4400 Silicone Rubber: Welcome

Varglas ES-4400
Silicone Rubber Sleeving

Varglas ES-4400 Silicone Rubber sleevings are produced by curing a specially compounded silicone gum with a select catalyst on a continuous length of fiberglass braid. Most silicone rubber is characterized by its capability of performing satisfactorily at elevated temperatures. In addition to providing superior dielectric and thermal protection, at less weight, Varglas ES-4400 was developed to meet unusual fluid and flame resistance requirements. Its high temperature performance places it in a 220°C classification.

Class: 220 R (-73°C to +220°C) (-100°F to +428°F)

Dielectric Strength Grade(s): A-1 B-1 C-1

Varflex's coated electrical insulated sleeving coated fiberglass light weight design with superior dielectric and thermal protection. Solution for use in medical and surgical equipment, aircrafts and transportation
Varglas ES-4400 Silicone Rubber: List
Varglas ES-4400 Silicone Rubber: Image


Varglas ES-4400 Silicone Rubber sleevings conforms to, and is listed on the Qualified Products List for, MIL-l-3190/8, latest revision (Grade A). It also exceeds the requirements of NEMA TF-1, Type 5; and ASTM-D372.

Under the Component Program of Underwriters Laboratories, Grade A Varglas ES-4400 Silicone Rubber is recognized for 200°C, 600 volt service and complies with VW-1 flammability requirements under UL File #E63450 (VW-1 compliance of Grades B through C-1 is covered under UL File #E53690). CSA International certified the use of Grade A for 200°C, 600 volt service and flammability requirements under CSA File #LR58486 VW-1. Varglas ES-4400 is incorporated in systems work, per UL Safety Standard 1446, to facilitate product acceptance by UL.


Varglas ES-4400 Silicone Rubber sleevings displays superior dielectric strength, high and low temperature performance, excellent fluid and flame resistances. These characteristics make it ideally suited for use in industrial instrumentation for measurement, analysis and control, surgical, medical, optical instruments as well as electronic machinery and equipment. It's lighter weight provides an additional performance advantage making it ideal for aircraft and other transportation equipment.


Standard Colors

AWG #24 through 2” l.D.

Other sizes subject to inquiry.

Blue-gray and tan. Other colors made to order.

Standard Packaging

Coils, spools or 36” lengths at manufacturer’s option, unless otherwise specified. There is no cutting charge for 36” lengths, but lengths other than 36” are subject to cutting charges.
Sizes over 1” l.D. are generally supplied in 36” lengths.

Varglas ES-4400 Silicone Rubber: List
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