(Hon&Guan 4" Grow Tent Ventilation Inline Duct Fan Carbon Filter Hydroponic Kit. Hon&Guan 3-8in Adjustable Round ABS Air Vent Grille Louver Ventilation Cover UK. 4)thi s Hon&Guan ventilation suits for HVAC, Bathroom, Greenhouse, Grow room and Tent and so on.
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