IHCO MICA STRIP HEATERS are the most versatile of all types of heaters for industrial and commercial applications. They are used in a wide variety of environments. Rust-resistant sheath– zinc-impregnated steel for excellent heat transfer (18 gauge steel pressure plate, 24-gauge shell), Mica insulation– high dielectric and mechanical strength; no breakdown under adverse conditions, Nickel-chromium resistance ribbon– precision wound on custom machines to ensure proper resistance rating.