SIP hátalari frá Grandstream GSC3505 sem hægt er að nota fyrir kallkerfi frá öllum helstu símkerfum.

• Speaker with HD acoustic chamber
• Features SIP paging, multicast paging, callwaiting with priority override
• Full-band and wide-band audio codec support including Opus & G.722
• Integrated dual-band 802.11 a/b/g/n WiFi and Bluetooth
• One 10/100Mbps network port with PoE/ PoE+