Abstract: An improved magic tee constructed to maximize the power that can be transferred from the H-plane arm to the collinear side arms and vice versa. The matching post is designed to maximize the breakdown voltage between the post tip and the walls of the E-plane arm. This is accomplished by selecting the post diameter to produce a ratio of the E-plane arm height to post diameter which develops a characteristic impedance corresponding to that of a coaxial transmission line constructed to withstand the maximum breakdown voltage between the transmission line center conductor and conductive shielding for a given shield separation.