UL stands for Underwriters Laboratory. It is the leading independent organization responsible for setting safety standards and testing for a wide range of industries and appliances. If an appliance or device has a UL listing, it means it has been tested to UL standards as they apply to a particular industry or application and it has passed. The tests are stringent and rigorous in order to assure that only safe and reliable products receive the UL listing. A UL listing informs the consumer that the product he is buying has been suitably tested and found acceptable for the application for which it was intended.
Stainless steel pipe, either rigid or flexible, made for relining flues of masonry chimneys when the original clay liner has cracked or broken. May also be used to create a lining in a masonry chimney that was made without a clay liner.
Protective coverings for chimneys usually made of aluminum, galvanized or stainless steel, or copper. Most chimney caps have a mesh screening that serves the dual purpose of spark arrestor and barrier against animals. Chimney caps also prevent rain from entering the flue of the chimney.
A device installed at the top of a chimney for the purpose of sealing the flue shut when the fireplace is not in use. They are often used as replacements for throat dampers that are installed just above the firebox when a masonry chimney is built. Lyemance and Lock-Top top-sealing dampers are as much as 90% more efficient than throat dampers because they provide a silicone rubber gasket seal rather than metal to metal.