Critical properties of systems that undergo He ignition in binaries with an accretor of an initial mass of 0.7 M_⊙. The figure shows (a) the density of the He layer at the location of ignition, (b) the total mass of He accumulated on the WD, (c) the time-averaged accretion rate from the time when the accretion rate was greater than 10⁻¹⁰ M_⊙ yr⁻¹ until the He ignition and (d) the peak accretion rate at which the WD gains mass. Systems classified as double detonation supernovae experience steady accretion with lower average and peak rates, leading to the accumulation of more He and ignition at a denser (> 10⁶ g cm⁻³) layer.