  We derive a new inequality that is necessary and sufficient to show
EPR-steering in a scenario employing only correlations between two arbitrary
dichotomic measurements on each party. Thus the inequality is a complete
steering analogy of the CHSH inequality, a generalisation of the result of
Cavalcanti et al, JOSA B, 32(4), A74 (2015). We show that violation of the
inequality only requires measuring over equivalence classes of mutually
unbiased measurements on the trusted party and in fact assuming a general two
qubit system arbitrary pairs of distinct projective measurements at the trusted
party are equally useful. Via this it is found that for a given state the
maximum violation of our EPR-steering inequality is equal to that for the CHSH
inequality, so all states that are EPR-steerable with CHSH-type correlations
are also Bell nonlocal.
