(Hon&Guan 4" Inline Duct Fan Set for Duct Ventilation Installation Exhaust System. 3/4/5/6In Flexible Ducting Vent Pipe Aluminum Foil PVC Duct Hose Ventilation 5m. 4)thi s Hon&Guan ventilation suits for HVAC, Bathroom, Greenhouse, Grow room and Tent and so on.
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