The setup is based on the break even point of the put sale so position size should be calculated based on this setup:
I do not expect to own shares off this put sale--although I would like to own ALXN at these levels--because I believe this is just a corrective pull back from the completion of a 5-wave move. The reason my stop is so tight is because I believe there are 5 significant support levels above my stop increasing the likely hood of a bounce if I get put the shares. Those levels I believe are: 125.56, 125.32,124.92, 124.15, and the 50SMA.
If i were lucky enough to get put the shares and the a new low higher low was formed at or near one of the 5 support levels mentioned, then this trade would have the potential to be very profitable