This specification establishes the requirements for two types of clear silicone varnished glass fabrics in the form of sheets, rolls, and tapes for use as electrical insulation. Type A fabrics are used where electrical properties are primarily required, while Type B fabrics are used where physical properties are primarily required. The glass fabric shall be treated with a baking type of silicone varnish so as to penetrate the fabric and produce a smooth, non-tacky surface, substantially free of wrinkles, creases, blisters, and other imperfections. The products shall be sampled, tested, and conform accordingly to specified physical (breaking strength), dimensional (nominal thickness, width, length, and core), thermal (temperature index), electrical property (dielectric strength, breakdown voltage, and dissipation factor and permittivity) requirements.