  We discuss first order transitions for systems in the Ising universality
class. The critical long distance physics near the endpoint of the critical
line is explicitly connected to microscopic properties of a given system.
Information about the short distance physics can therefore be extracted from
the precise location of the endpoint and non-universal amplitudes. Our method
is based on non-perturbative flow equations and yields directly the universal
features of the equation of state, without additional theoretical assumptions
of scaling or resummations of perturbative series. The universal results
compare well with other methods.
