The F10X is not a traditional wrist brace; it doesn't have any metal supports. It's supposed to increase your wrist strength by up to 10%.
If you require that your wrist be prevented from bending backward, I would look elsewhere. If you don't want one of the Mongoose-type supports, but something more like a traditional bowling glove, I can recommend the Ebonite Positioner and the Master Wristmaster II Excel.
The Wristmaster II Excel has removable metal braces in both the palm and wrist. I always remove the palm support, as I don't like the way it feels, and the way it changes the position of the ball in my hand.
Hope this helps!
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seadrive
Cogito ergo bowl