G-10/FR4 Garolite Laminate

G-10 (often written G10, and sold by some distributors as Garolite) is a glass/epoxy laminate that offers a superior strength/size ratio in addition to its self-extinguishing properties. In addition to its high mechanical strength, it exhibits good dielectric loss and electrical strength under a range of dry and humid conditions. The flame resistance is Class I in accordance with NEMA test method 7.11. Read our G-10 Guide.

What Is G10 Material? A History of G-10 and FR-4

G10 material is a thermosetting industrial laminated plastic made of woven glass cloth in an epoxy resin matrix. First introduced in the 1950s, G-10 was the original glass-epoxy laminate used in printed circuitry. The high strength, excellent electrical properties, and chemical resistance of G-10 make for a very versatile material that is now being used in a wide variety of applications.

Today most of what is called G-10 is actually FR-4, the flame retardant version of G-10. This explains why you will also see the material designated G-10FR. This means FR-4. The material FR-4 can usually be used where G-10 is called out, however, G-10 should not be used where FR-4 is specified.

Material Characteristics and Performance

G-10/FR4 is produced from woven glass cloth reinforced with an epoxy resin matrix. Its key G10 material properties, high mechanical strength, low moisture absorption and dependable dielectric properties, hold across a wide range of operating conditions. FR-4 includes flame retardant additives and meets Class I requirements under NEMA test method 7.11, making it suitable for applications where fire performance is a design consideration.

Current, Inc. offers G10 sheet, G10 tubes and rod in multiple thicknesses, sheet sizes, and tubular configurations. Standard G10 sheets measure 36″ × 48″ and 48″ × 96″, with cut to size options available. Tubing is offered in a range of inside and outside diameters to support structural, electrical, and mechanical assemblies. Sanded surfaces can be provided to support bonding, machining, or secondary finishing operations.

Fabrication Support for Industrial Applications

G-10/FR4 (Garolite) is commonly machined into spacers, insulators, brackets, enclosures, and precision components. Current, Inc. supports routing, drilling, turning, and shaping operations to deliver parts that meet tight dimensional requirements. Our team works with both prototype quantities and production scale orders, ensuring consistent tolerances and repeatable performance across multiple builds.

Applications Across Multiple Industries

G10/FR4 is used in electrical insulation systems, transformer components, switchgear, aerospace hardware, marine equipment, and industrial machinery. Its combination of strength, electrical stability, and chemical resistance makes it suitable for demanding environments where reliability and long term performance are required.