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TOI 560.01 is a mini Neptune orbiting a young (400-600 Myr) and nearby (32 pc) K star comma the first and only mini Neptune with measured helium absorption from its photoevaporating atmosphere. We propose to observe three transits of the planet with STIS-G140M in order to measure Lyman alpha absorption from the outflow. Photoevaporation is especially interesting to probe in this regime because it predominantly occurs in the active youth of a star.s life comma creating the ''Fulton gapd_comma in radius which divides super-Earths (1--1.8 REarth) from mini-Neptunes (2--3 REarth). These observations will allow us to measure the size comma shape comma and kinematic structure of the exosphere comma constrain the mass loss rate comma and evaluate the magnitude of any visit-to-visit variability in the outflow structure. The combination of Lyman alpha and He I 1083 nm observations will provide stringent constraints on hydrodynamical models. These two wavelengths provide complementary informationdoublePoint Ly alpha probes high-velocity hydrogen in the tenuous outer reaches of the exosphere comma while helium probes low-velocity helium in the denser part of the exosphere comma much closer to the planet surface. Finally comma recent TESS observations indicate that there may be another transiting planet in the TOI 560 system on an exterior orbit comma although it has not yet been confirmed. Multi-planet systems are ideal for studying mass loss because the two planets share the same high-energy irradiation history and similar formation histories comma making comparative planetology possible.