A full line of Type-B gas vents is designed for quick installation on any residential job. The B-Vent is available in 3-24 inch diameters for typical residential installations; for light commercial, institutional, and industrial installations the manufacturer offers sizes up to 30 inches in diameter. The B-Vent line features hemmed outer and inner liners, allowing quicker installation and reduced injuries from sharp edges. Its patented positive twist locking system provides a tight lock that allows easy assembly or disassembly without tools or damage. Swivel tees, wyes, and elbows allow 360-degree continuous rotation for easy repositioning. The vent is evaluated and listed by Underwriters Laboratories Inc. (UL) to match with a number of other UL-listed, round gas vent products, making it versatile enough to be used with systems from several other manufacturers, said the company.