hon&guan 4" duct connector, plastic straight pipe flange for heating cooling ventilation system(100mm). hon&guan <b>hon&guan, professional ventilation equipment manufacturer</b><br> hon&guan which focuses on the r&d manufacturing of air replacement, fresh air ventilation and ventilation equipment,<br> is a modern high-tech enterprise with main products such as mixed flow inline duct fan, ventilation fan, ac, dc fans and ventilation accessories.<br><br> <b>product application:</b><br> perfectly suited for ducting your tumble dryer, bathroom or kitchen extractor fan, hydroponics, in-line extract fans, or cooker hood and so on. <br><br> <b>package include:</b><br> 1x hon&guan 4 inch duct connector