The low-gravity of 2MASS J2126-8140 indicates that the object is somewhat inflated, and still in the process of cooling and contracting in size. The separation of 2MASS J2126-8140 from its host star, TYC9486-927-1, is estimated to be over 4500 AU. This gives 2MASS J2126-8140 the wides orbit known for any planetary-mass object. So far, only a handful of such objects have been discovered. Some of these objects include WD 0806-661B, a planetary-mass object with 6 to 9 times the mass of Jupiter at 2500 AU from its host star; and GU Psc b, a planetary-mass object with 9 to 12 times the mass of Jupiter at 2000 AU from its host star.
Deacon et al. (2016), “A nearby young M dwarf with a wide, possibly planetary-mass companion”, arXiv:1601.06162 [astro-ph.EP]