The GSC3505 is a one-way public address SIP speaker that enables offices, schools, hospitals, buildings, and other facilities to develop powerful public address broadcast solutions that expand security and communication. The GSC3505 provides HD audio functionality thanks to its 8W HD speaker. It is also compatible with built-in Bluetooth, whitelist and blacklist devices to easily block unwanted calls, SIP and multicast paging and integrated dual-band Wi-Fi.