an oxidized flavin + NADH + 2 H(+) => a reduced flavin + NAD(+)
an oxidized flavin + nadh + 2 h(+) => a reduced flavin + nad(+)
an oxidized flavin + NADH + 2 H(+) => a reduced flavin + NAD(+)
an oxidized flavin + nadh + 2 h(+) => a reduced flavin + nad(+)