SL1100 24 Button Full-Duplex Backlit IP Display Tel (Black)Features include:- Abbreviated Dialing/Speed Dial- Account Code Forced/ Verified/Unverified- Account Code Entry- Alarm- Alarm Reports- Alphanumeric Display- Analog Communications Interface (ACI)- Ancillary Device Connection- Answer Hold/Automatic Hold- Attendant Call Queuing- Automatic Release- Automatic Route Selection (ARS/F-Route)- Background Music- Barge-In- Battery Backup - System Memory- Battery Backup - System Power- Built-in Automated Attendant- Call Arrival (CAR) Keys- Call Duration Timer- Call Forwarding- Call Forwarding with Follow Me- Call Forwarding Off-Premise- Call Forwarding/Do Not Disturb Override- Call Monitoring- Call Redirect- Call Waiting/Camp-On- Callback- Caller ID Call Return- Caller ID- Caller ID - Flexible Ringing- Caller ID - Shared Logging- Central Office Calls Answering- Central Office Calls Placing- Class of Service- Clock/Calendar Display/Time and Date- Code Restriction/Toll Restriction- Code Restriction Override/ Toll Restriction Override- Code Restriction Dial Block/ Toll Restriction Dial Block- Conference- Conference Remote- Conference Voice Call/ Privacy Release- Continued Dialing- Data Line Security- Delayed Ringing- Department Calling- Department Step Calling- Dial Pad Confirmation Tone- Dial Tone Detection- Dialing Number Preview- Digital Trunk Clocking- Direct Inward Dialing (DID)- Direct Inward Line (DIL)- Direct Inward System Access (DISA)- Direct Station Selection (DSS) Console- Directed Call Pickup- Directory Dialing- Distinctive Ringing Tones and Flash Patterns.