Tillman® ArcDefender Thermofelt 16 oz. Plumbers Pad. FM Approved Welding Pad. 16 oz., Thermofelt. Light duty welding, light sparks and spatter. Non-flammable, non-melting, non-shrinking, scratch free. Smoking and loss of tensile strength will occur when subject to molten metal. Not designed for stress relief. 1800ºF working temperature. 12″ x 12″ size, perfect for small spaces.