  We describe an analytic distribution function of a finite, oblate stellar
system that is useful for the practical modelling of dark halos. The function
is determined by lowering Evans's (1993) distribution function of a flattened,
cored isothermal system in analogy to the lowering of the singular, isothermal
sphere in the definition of the King (1966) models. We derive analytic
expressions of the density, maximal streaming velocity and velocity dispersion
profiles as a function of the potential. As for the King models, the potential
must be calculated numerically. We also present a recipe for generating N-body
realizations of this distribution function and examine the stability in three
models with dimensionless spins $\lambda=$0.0, 0.05 and 0.18 using N-body
simulations with 50,000 particles. The $\lambda=0.18$ model is unstable to the
formation of a triaxial bar within $\sim 5$ King radii while the other models
appear stable. We conclude that the slowly rotating systems are useful for
modelling flattened dark halos.
