The Selkirk 4 in. Type B Terminator Kit (4-Pack) offers many convenient features, such as a sturdy galvanized-steel outer pipe, die-formed ends, and easy-to-use lock tabs. This kit is suitable for residential, light-commercial, and industrial gas appliances. Its durable galvanized-steel outer pipe and internal spacing bends create an insulating air space, while die-formed ends ensure consistent sizing for strong, secure joints. The lock tab feature eliminates the need for sheet metal screws and can be easily engaged by installers. It meets all safety standards and has been tested and listed per UL 441 for single- and multi-story installations in accordance with NFPA 54 and NFPA 211 guidelines.