3M„ Glass Cloth Electrical Tape 27 This 3M Glass Cloth Electrical Tape 27 is designed to operate in 600-volt dry applications requiring high mechanical strength and resistance to high temperatures. Glass cloth electrical tape with rubber thermosetting adhesiveFor high temperatures up to +150 CIt consists of a glass fiber-reinforced polyester filmExtremely high tensile strengthHigh dielectric strengthFlame retardant to UL510Applications include a heat-stable insulation for furnace and oven controls, motor leads and switches