This talk is the continuation of the preceding IFS by Gaston. We have been introduced to the Bernstein presentation of the affine Hecke algebra and a theorem has been announced providing an isomorphism of this algebra with the equivariant K-theory of the Steinberg variety with respect to the GxC*-action. I will start by a brief introduction to equivariant K-theory and recall the definition of the Steinberg variety in order to make this statement precise. The second part of the talk will be devoted to understanding this isomorphism in the case of SL2.