  In this note we discuss a few properties of transnormal Finsler functions,
i.e., the natural generalization of distance functions and isoparametric
Finsler functions. In particular, we prove that critical level sets of an
analytic transnormal function are submanifolds, and the partition of $M$ into
level sets is a Finsler partition, when the function is defined on a compact
analytic manifold $M$.
