Relation between the supernova ejecta oxygen yield and the ZAMS mass of different stellar evolution and supernova explosion models. The lower dashed line denotes the constraint-free lower limit on the oxygen mass (Eq. (22)), while the upper dashed line denotes the minimum oxygen mass assuming the NLTE conditions derived from the recombination line analysis (Eq. (24)). Binary evolution models are shown using circles and single massive star models are denoted by square markers. Models inconsistent with the estimated ejecta mass or not fully stripped of hydrogen are shown using unfilled symbols.