Hi, i've just studied the weak global Torelli theorem for K3, which states that, given two K3 surfaces $X$ and $Y$, they are isomorphic if and only there is an Hodge isometry between $H^2(X,\mathbb{Z})$ and $H^2(Y,\mathbb{Z})$.
I didn't find any example of application of this theorem, so i was wondering if you could point out some examples of K3 surfaces which are proven to be isomorphic by the existence of a Hodge isometry