Do you mean when they tech-roll? if yes when you tech roll there´s a small window where you can hit your oppontent, that´s called an ´´unholdable´´ i don´t know if you heard of those.
Free Step Dodge
Darkslay
Darkslay
However 3PP was a vanilla thing i´m not fullt aware if that still works the usual unholdable is 46K.