determine the effective temperature (T$_{\rm eff}$) and surface composition of both stars in the binary from the analysis of their spectra [@2010ASPC..435..207P]. As a result, DEBS provide the most stringent test available for the accuracy of stellar evolution models for many different types of star . Empirical relations between mass, density, T$_{\rm eff}$ and metallicity based on DEBS can be used to estimate model-independent masses and radii for low-mass companions in SB1 eclipsing binaries, e.g., transiting hot-Jupiter systems [@2011MNRAS.417.2166S] or brown dwarf or very low mass stars in eclipsing binaries with solar-type stars . DEBS are also useful as distance indicators because their absolute magnitudes can be accurately estimated from the radii of the stars combined with a calibration of the stars’ surface brightness against colour or T$_{\rm eff}$ [@2017ApJ...837....7G]. DEBS have been used to investigate the systematic errors in parallax measurements for the Gaia DR1 data release [@2016ApJ...831L...6S], and to accurately measure the distance to the Magellanic Clouds [@2013Natur.495...76P; @2014ApJ...780...59G].

The Kepler K2 mission is providing very high quality photometry for thousands of moderately bright stars in selected regions of the sky (“campaign fields”) near the ecliptic plane [@2014PASP..126..398H]. Each campaign field is observed almost continuously for up to 