So why do these have EOL that ALWAYS seems to be 2AM to scare the Bejesus out of you? Try to go back to sleep after trying to decide if alarm is real or crashing? They have 7 year lifespan so it is due. Just haven't looked at date in years. So off to hardware store in morn ... oh wait they are not open at 2AM! Its a combo CO, CO2, explosive gas monitor so hope they have one. Hard to find one with this combo.