16KHz. Operating Temperature: 0 ～ 45 ℃. Measurements: 144 * 144 * 34.1 mm. Network Horn Audio Speaker GEN-6391A03 Power Supply: DC24V/2.7 A or POE. Interaction Procedure: TCP/IP, UDP, SIP, ONVIF. Signal-to-Noise Proportion: > 80dB. Frequency Feedback: 100Hz https://communicationssystem39073.ttblogs.com/9551751/just-how-an-ip-paging-system-boosts-emergency-situation-response-in-workplaces