These are great fans. Why no one has reviewed them I have no clue? I put them in my Freewing A-10 and wow what a sound and much better handling plane. I recommend them for all 64mm EDFs. The balance is that good. I have this fan in my BAE hawk too. Great sound. No more winneing sound!10 blades ?? I can go crazy with things like that , you'll gain almost twice the power from your engine !!Great product - mine had 68mm moulded in them but when compared to the 68mm version you can see the tips have been sanded down and it is indeed a 64mm - great for quietening the 64mm screamers with the realistic jet whoosh.I am building a monstor 64mm EDF jet. I needed this 10 blade to properly evaluate the thrust ratio needed.