Bought this spinner to use on a PZ Spitty. The back plate accepts the prop center sizers that come with APC-E type props. The prop adapter included is sized for a 3mm shaft motor but not to worry as the spinner will slide right over the stock PZ Spitfire or Bf-109 prop adapter without any fuss or mods and either prop nut (the PZ ones) will fit under the cone easily. Great fit and nice finish. Well made product that actually will work!!