AS-HS30W white horn speaker is applicable to indoor or outdoor, the horn speaker is good in a PA system when you need your sound heard far and wide. It provides intelligible voice paging and tone signaling for your security alarm or sound system applications. Intallation Environment: Avoid installing the speaker in locations which vibrate considerably, or under environments easy to be oil-contaminated. For outdoor installation, it is recommended that they are installed under roofs, eaves, or in other locations not directly exposed to rain or snow. white horn speaker is applicable to indoor or outdoor, the horn speaker is good in a PA system when you need your sound heard far and wide. It provides intelligible voice paging and tone signaling for your security alarm or sound system applications. Installation Environment: Avoid installing the speaker in locations which vibrate considerably, or under environments easy to be oil-contaminated. For outdoor installation, it is recommended that they are installed under roofs, eaves, or in other locations not directly exposed to rain or snow.