hg power 16.5 foot duct silencer flexible ducting hose noise reducer hose silencer for inline duct fan (5 inch, white) hg power <b>feature:</b> <br><br>· inner duct: perforated alium foil <br>· middle layer: glass wool (20kg/m3 density) <br>· outer sleeve: 1 alium + 1 polyester lamination <br>· tempreture range:-30°c to 150°c <br>· color: white <br>· size: 5 inch x 16.6 foot <br><br>1)thick layer of white pvc on this ducting prevents light leaks. works with exhaust and intake fans, carbon filters and <br>hooded lights which are 4" in diameter. <br>2)under the white pvc layer our ducting is built with 2 layers of aluminum foil with a layer of pet and steel wire helix to <br>preserve the shape,keep your ventilation system free of rips and pin holes. <br>3)designed for reducing noise from fans and carbon filter systems, can decrease the noise by up to 50%. <br>4)this hg power ventilation suits for hvac, bathroom, greenhouse, grow room and tent and so on.