A coolable airfoil 46 has heat transfer members disposed in the rearmost section of the trailing edge region which include a row of chordwisely extending flow dividers 170. At least one of the dividers 170 has sidewalls facing radially such that the sidewall 176 facing inwardly has a larger angle of diffusion alpha than that beta of the sidewall facing outwardly 178. The inwardly facing wall 176 of a radially outwardly divider 170o may have an angle alpha 2 which is greater than that alpha 1 of that of a radially inner divider 170i. <IMAGE>
