Quick overview from the supplier:
Grandstream DP722 DECT, 10 SIP, 10 Lines, Silver
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Supports a range of up to 350 meters outdoors and 50 meters indoors when used with the DP752 (300 meters outdoors when used with DP750)
1.8 inch (128x160) color LCD with 2 programmable soft keys
Offers 20 hours talk time and 250 hours standby time
Supports up to 10 SIP accounts and 10 lines per handset as well as 3-way conferencing
Push-to-talk via a configurable button
Seamless 1-touch door control with Grandstream’s GDS series of Facility Access devices
HD audio on the speakerphone, handset, and headset jack
Software and firmware updates over-the-air
https://www.grandstream.com/products/ip-voice-telephony/dect-cordless/product/dp722
