  We present an overview of the ASTRO-H (Hitomi) Soft X-Ray Spectrometer (SXS)
and the X-Ray Imaging and Spectrometer Mission (XRISM) {\it Resolve}
spectrometer. In each, a 36-pixel X-ray micro-calorimeter array operated at 50
mK covers a $3 \times 3$ arc-minute field of view. The instruments are designed
to achieve an energy resolution of better than 7 eV over the 0.3 -- 12 keV
energy range and operate for more than 3 years in orbit. Actually, the SXS
achieved the energy resolution of $\sim$5 eV in orbit, but it was lost after
only a month of operation due to the loss of spacecraft attitude control. For
the recovery mission, XRISM will be equipped with the {\it Resolve}
spectrometer which has mostly the same design as SXS and is expected to have
the same in-flight performance.
