Scare off would-be intruders and alert the neighborhood with this wireless 105 dB indoor/outdoor siren. Loud 105 dB siren makes sure the alarm is heard when a security risk is detected. IP65 weather-resistant design, so the siren can be used indoors and in sheltered areas outdoors too. Easy to install without the need for tools or professional installation. Requires homebase to operate. Compatible with HomeBase S380 and S280. One App Controls All. Links to HomeBase and the eufy Security app. Easily get notifications and check the battery status. Takes two CR123 batteries which last up to 2 years.