  Main-sequence bolometric corrections (BC) and a standard BC-Teff relation are
produced for TESS wavelengths using published physical parameters and light
ratios from SED models of 209 detached double-lined eclipsing binaries. This
and previous five-band (Johnson B, V, Gaia G, GBP, GRP) standard BC-Teff
relations are tested by recovering luminosity (L) of the most accurate 341
single host stars (281 MS, 40 subgiants, 19 giants and one PMS). The recovered
L of photometry is compared to L from published R and Teff. A very high
correlation ($R^2$ = 0.9983) is achieved for this mixed sample. Error
histograms of recovered and calculated L show peaks at 2 and 4 per cent
respectively. The recovered L and the published Teff} were then used in $L = 4
\pi R^2 \sigma Teff^4$ to predict the standard R of the host stars. Comparison
between the predicted and published R of all luminosity classes are found
successful with a negligible offset associated with the giants and subgiants.
The peak of the predicted R errors is found at 2 per cent, which is equivalent
to the peak of the published R errors. Thus, a main-sequence BC-Teff relation
could be used in predicting both L and R of a single star at any luminosity
class, but this does not mean BC-Teff relations of all luminosity classes are
the same because luminosity information could be more constrained by star's
apparent magnitude $\xi$ than its BC since $m_{Bol} = \xi + BC_\xi$.
