Roost offers a 1-year hardware warranty from the date of purchase from getroost.com or authorized resellers, currently only Lowes in the United States. We are unable to honor warranties on batteries purchased from other channels, including eBay or unauthorized sellers reselling Roost products via channels such as Amazon.com. We are not able to offer support or warranty on any products purchased in the United States or United Kingdom and shipped or taken to a country where we do not have an authorized reseller.
Please note that we do not offer any warranty for Roost batteries used in smoke or combined smoke/CO alarms older than 10 years based on the manufacturing date on the alarm. If an alarm has no manufacturing date, we cannot warrant the use of the Roost Smart Battery in this alarm.
Please see our Help Center article: When should I replace my smoke alarm or smoke/CO alarms?