... I. Features of DJF(a) series exhaust fan: 1. Fan blades are made of stainless steel, having strong ... sizes make installation convenient. There are nine kinds of fan size: 620mm (24″), 780mm(30″), 830mm(32 ... 1000mm(39″), 1100mm(43″), 1220mm(48″), 1380mm (54″), 1530mm(60″).6. We can customize A type or ... III. Technical parameters of DJF(a) series exhaust fan: FansizeMotor rotational speed(rpm)Air flow (m3/ ...