Here is a review left by a customer on a product. Would you say he was satisfied or dissatisfied?
Title: Functional, Inexpensive Neccessity
Review: We've used these for years without problems.They run on batteries(2 AA included) or plug, and produce an annoyingly, loud 85dB siren. The instructions are easy to follow- a no brainer- and it's a no brainer that along with smoke alarms and fire extinguishers we should have these in our homes.They recommend one alarm on every level and every sleeping area. They list the sources of CO, e.g. chimney, garage, furnace of course, heaters, dryer, range and grill.They say they last 7 years, and it let's you know when it's shot. I think, in general, we replace them after about 4-5 years.
