250mm AC inline duct fan 1.Heat protection 2.Long life time 3.Runout of ... than 1mm 4.All material accord to ROHS 250mm AC inline duct fan:The housing made of SGCCThe impeller made of PA66 (FR ... for blow, exhaust, circle, renew and filtration could be used in hotel marketplace gymnasium supermarket store room and most of public ... housing, impeller, motor, base and connection box. 250mm AC inline duct fan