US made Stratus 20 from Vincero Design is brilliant for cross.
The wedge shaped carbon bracket secures to the frame’s normal bottle mounts and has a strong magnet inset into it.
The bottle has a hard plastic inset moulded into it which fits over the bracket and has another magnet inset into it.
When on the bike the bottle is held firmly in place by the wedge shape and the magnets.
Best though, is when the bottle is not attached, there is no cage to get in the way when picking up and shouldering the bike.
It’s super convenient to not have to remove for weekly training and racing and the magnets are strong enough to hold the bottle in place off-road.
They are not widely available and are fairly expensive, but are a really useful addition to a cross bike which is used for racing and training.
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