Blade Diameter: 68.3mm / 2.68inch Outer Case Diameter: 73mm Wall Thickness: 1.53mm EDF Length: 59mm Front Shroud Diameter: 83mm Motor Mount Holes: (from 18mm & 22mm) Blade Type: 6 Shaft Size: 4mm This EDF will take a motor with a maximum diameter of 28mm.(see related items)