The pontoon with the Yamaha 250 came with a Apollo prop. It's a
stainless 14x21, and has the XHS system that uses an adapter that fits
the prop shaft of the motor, a rubber/metal/plastic hub, and then the
prop fits on that. It makes the props universal, you just buy the hub
kit for your motor.

Anyone have any experience or feedback to offer on these? I ask
because I evidently stripped the hub on mine Sunday. Running in 60
feet of water at 3600 rpm, I throttled up to about 4500, and as it was
coming up the motor suddenly wound up and bounced off the rev limiter
as the boat fell flat. Shut down, checked the prop, it's perfect,
started back up carefully pushing the throttle forward, and it slips
again. Was headed back in anyway, so I idled back in.

Will be pulling the prop this evening, and I have a new hub to
install. The dealer tells me they've seen one other one that chewed
the hub up recently for no reason.

I'm thinking of pushing for a new Yamaha prop. Don't trust the Apollo
now.