Known exact results include the conformal dimensions of the fields that detect whether a point belongs to an FK cluster or a spin cluster. In terms of Kac indices, these conformal dimensions are respectively 2 h 0 , 1 2 and 2 h 1 2 , 0 , corresponding to the fractal dimensions 2 − − 2 h 0 , 1 2 and 2 − − 2 h 1 2 , 0 of the clusters.