11 leaves 704mm diameter ring fan fan blade root comes with guide plate and air separator, increase fan efficiency basic technical parameters: & nbsp; fan type & nbsp; flow to strengthen the annular fan & nbsp; fan maximum diameter & nbsp; 704mm & nbsp; fan installation diameter & nbsp; 692mm & nbsp; axial fan with a total thickness of & nbsp; 126.5mm & nbsp; fan installed thickness & nbsp; 90mm & nbsp; fan material thickness & nbsp; 5mm & nbsp; installation hole number & nbsp; & nbsp; installation hole pitch circle diameter & nbsp; 200mm & nbsp; installation check the diameter of the mouth of the & nbsp; 180mm