Hubs are a super important part of your drivetrain, we have been playing around with our cassette hubs that have an exclusive drive mechanisim that offers instand engagement and a failsafe mechanisim to keep you from ever faceplanting when a retaining spring goes. Currently the hubs are not in production so they are not available for sale. But we are hoping to find a good machine shop that can offer us the quality we are demanding at a price that we can afford. Please keep checking back for details.