
The Kastaplast Grym X is the overstable side of a 12-speed — zero turn, three of fade.
No turn at all means it will not flip regardless of how hard you throw it, and three fade means the ending is never in doubt. That is the definition of a utility distance driver: wind, forced hyzers, and flex lines that have to come back. Five glide gives it enough air time for the fade to work through rather than dumping immediately. This is a disc for a strong arm that wants predictability over maximum distance. In calm air, a neutral 12-speed will fly further.
How much the Grym X turns and fades depends on how hard it is thrown. These three shapes are drawn from the manufacturer’s numbers, not from measured throws.
Birdie Bot