1/2" high-temperature, ultra-conformable fiberglass rope, they're flexible and will conform to uneven surfaces. The looser construction also makes them more likely to absorb liquids. Push them into the groove that's commonly built into oven doors, furnaces, and tanks. These high quality fiberglass rope resist bleach, solvents, and most acids (do not use with hydrofluoric acid, hot phosphoric acid, and wet hydrogen chloride). CAUTION! Always use proper protection when working with fiberglass. Avoid skin and eye contact.