A first commercial toroidal prop at 239usd. Performance should be better than a jet and safe without duct as demonstrated by the merciless “courgette test”.
https://efoilsolutions.com/products/toroidal-propeller-beta-version
This propeller (…) was tested in a lab environment with Lift Efoils under variable conditions. Better performance of up to 25% compared with the Lift stock Aluminum prop may be achieved at cruise speeds of up to 17 MPH. You should be able to increase your riding time
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If you ride a board other than a Fliteboard or Lift, please let us know and we will adapt this prop to your board for no additional cost.