  Some of the quiet solar magnetic flux could be attributed to a small-scale
dynamo (SSD) operating in the convection zone. An SSD operating in cool
main-sequence stars is expected to affect the atmospheric structure, in
particular the convection, and should have observational signatures. We aim to
investigate the distribution of these fields as well as their effect on
intensity characteristics, velocities and spatial distribution of kinetic (KE)
and magnetic energy (ME) in the lower photosphere of spectral types F3V, G2V,
K0V and M0V using 3D radiative-MHD simulations. PDFs of field strength at the
$\tau=1$ surface are quite similar for all cases. The M0V star displays the
strongest fields, but relative to the gas pressure, the fields on the F3V star
reach the largest values. All stars display an excess of horizontal field
relative to vertical field in the middle photosphere, with this excess becoming
increasingly prominent towards later spectral types. These fields result in a
decrease in upflow velocities, slightly smaller granules as well as the
formation of bright points in intergranular lanes. The spatial distribution of
KE and ME is also similar for all cases, implying a simple pressure scale
height proportionality of important scales. SSD fields have rather similar
effects on the photospheres of cool main-sequence stars, namely, a significant
reduction in convective velocities as well as a slight reduction in granule
size, and concentration of field to kG levels in intergranular lanes associated
with the formation of bright points. The distribution of field strengths and
energies is also rather similar.
