Quick overview from the supplier:
Grandstream GRP2601, 2 SIP,2 Line, no PoE, Black
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2 SIP account, 2 lines
GDMS online device management and provisioning
5-way audio conferencing for easy conference calls
Equipped with noise shield technology to minimize background noise
Electronic Hook Switch (EHS) support for Plantronics, Jabra, and Sennheiser headsets
Enterprise-level protection including secure boot, dual firmware images and encrypted data storage
https://www.grandstream.com/products/ip-voice-telephony-carrier-grade-ip-phones/grp-series-essential-ip-phones/product/grp2601p
