In 13-limit just intonation, 55/39 is the smaller gassormic tritone, measuring about 595.1¢. It is 275/273 (gassorma, about 12.6¢) sharp of 7/5, and is the interval between 13/11 and 5/3. Its inversion is the larger gassormic tritone, 78/55, and the interval that separates them is the small comma 3042/3025, about 9.7¢. This difference can be negligible, and tempering out this comma allows the 600¢ half-octave to function as both gassormic tritones. Thus, every even-numbered EDO system contains a close approximation to these intervals.