Companion properties and presence of radio eclipses of black widow systems for which the optical light curves of irradiated companions have been modelled with ICARUS. Higher irradiation luminosities and Roche-lobe filling factors are preferred for eclipsing black widow systems compared to non-eclipsing systems. The dashed line in the bottom panel denotes the companion radius for which physical eclipses would occur. The properties of PSR J1653−0158 are based on two different light curve models (see Nieder et al. 2020 for details).