Brand: Grandstream Model :  Grandstream GRP2601 Type    :  IP Phone Number of phone Line :  2 Line Caller ID                              :  Yes Call Waiting Caller ID    :  Yes IP Phone GrandStream Grade HD GRP2601 2-SIP Conference Call               :  5-way audio conference calls Redial Button                   :  Yes Call Log                               :  800 Display                                :  LCD display Display Size                       :  2.21 inch Volume Control               :  Yes Hold Key                             :  Yes Mute Key                             :  Yes Navigation Key                 :  Yes Transfer Key                       :  Yes IP Phone GrandStream Grade HD GRP2601 2-SIP Network Protocol :  SIP RFC3261, TCP/IP/UDP, RTP/RTCP, RTCP-XR, HTTP/HTTPS, ARP, ICMP, DNS(A record, SRV, NAPTR), DHCP, PPPoE, SSH, TFTP, NTP, STUN, SIMPLE, LLDP, LDAP, TR069, SNMP, 802.1x, TLS, SRTP, IPv6 Network Interfaces     :  Dual switched auto-sensing 10/100 Mbps Ethernet ports, integrated PoE Auxiliary Ports              :  RJ9 headset jack Headphone Jack         :  Yes Speaker                           :  Yes Power Source.              :  Adapter Input Power                   :  100 - 240VAC 50 - 60Hz Output Power               :  +5VDC, 600mA Power Consumption :  3.84W Wall Mount                    :  Wall mountable Dimensions                   :  208 x 180 x 63.4mm (with handset) Weight (gm)                  :  650gm Feature:  2-SIP IP Phone, Hold, transfer, forward, 5-way conference, call park, call pickup, downloadable phonebook(XML, LDAP, up to 2000 items), call waiting, call log(up to 800 records), off-hook auto dial, auto answer, click-to-dial, flexible dial plan, hot-desking, personalized music ringtones and music on hold, server redundancy and fail-over, Certification: FCC, CE, RCM, IC Warranty: 1 year