I had to get one last year, I was just thinking about that today that it might come in handy for monitoring at home if one of us get sick... I got mine on Amazon too. Mine was $14, now it's double that! Pulse Oximeter https://www.amazon.com/dp/B00SCPB9KU/ref=cm_sw_r_cp_apap_NrSbr3upLEacC)