  We prove the finiteness of the Hofer-Zehnder capacity of unit disk cotangent
bundles of closed Riemannian manifolds, under some simple topological
assumptions on the manifolds. The key ingredient of the proof is a computation
of the pair-of-pants product on Floer homology of cotangent bundles. We reduce
it to a simple computation of the loop product, making use of results of
A.Abbondandolo- M.Schwarz.
