4 inch 100 caliber small air volume 130 cubic meters (single speed) 4 inch 100 caliber single speed black 4 inch 100 caliber single speed 4 inch 100 caliber double speed control black 4 inch 100 caliber double speed control 6 inch 150 caliber single speed black 6 inch 150 caliber single speed 6 inch 150 caliber double speed control black 6 inch 150 caliber double speed control black 6 inch 150 caliber double speed control 8 inch 200 caliber single speed 8 inch 200 caliber black 8 inch 200 caliber black 8 inch 200 caliber double speed control black 8 inch 250 caliber double speed control 12 inch 300 caliber double speed control black stepless variable speed EC motor 4 inch energy saving black stepless speed ec motor 6 inch energy saving 10 inch BPT10-17S 11 inch BPT10-18S 11 inch BPT10-21S 8 inch APB20-4-A 8 inch APB20-4-B 10 inch APB25-5-A 10 inch APB25-5-B