| Model | SIP-T23G | SIP-T21(P) E2 | SIP-T19(P) E2 |
| Download | Datasheet | Datasheet | Datasheet |
| LCD | 2.8" graphical LCD | 2.3" graphical LCD | 2.3" graphical LCD |
| Resolution | 132 x 64 | 132 x 64 | 132 x 64 |
| LCD Backlight | |||
| Line | 3 | 2 | 1 |
| PoE | (T21P E2) | (T19P E2) | |
| GigE | |||
| Wall Mounting | |||
| Foot Stand | 1adjustable angle | 1adjustable angle | 1adjustable angle |
| USB Port (2.0 compliant) | |||
| Ethernet Port | Dual-port Gigabit Ethernet | 2 x RJ45 10/100M Ethernet ports | 2 x RJ45 10/100M Ethernet ports |
| Handset Port (RJ-9) | |||
| Headset Port (RJ-9) | |||
| External Yealink AC Adapter (optional) | AC 100~240V input and DC 5V/600mA output | AC 100~240V input and DC 5V/600mA output (T21 E2: Standard/T21P E2: Optional) |
AC 100~240V input and DC 5V/600mA output (T19 E2: Standard/T19P E2: Optional) |
| Line Key | 3 | 2 | 0 |
| Memory Key | 3 | 2 | 0 |
| EXP50 Expansion Module (Accessory, pruchased separately) | |||
| Yealink EXP40 Expansion Module (Accessory, pruchased separately) | |||
| Yealink EXP20 Expansion Module (Accessory, pruchased separately) | |||
| Yealink EHS36 Wireless Headset Adapter (Accessory, pruchased separately) | |||
| Yealink YHS32 Headset (Accessory, pruchased separately) | |||
| Yealink Bluetooth Adapter BT40 (Accessory, pruchased separately) | |||
| Yealink Wi-Fi Adapter WF40 (Accessory, pruchased separately) | |||
| USB Recording | |||
| 3-way Conferencing | |||
| HD Voice | HD Speaker HD Handset |
HD Speaker HD Handset |
HD Handset |
| Wide-band Codecs | G.722, Opus | G.722, Opus | G.722, Opus |
| Narrow-band Codecs | G.711(A/µ), G.729AB, G.726, iLBC | G.711(A/µ), G.729AB, G.726, iLBC | G.711(A/µ), G.729AB, G.726, iLBC |
| LCD Type | Fixed | Fixed | Fixed |
| Operating System | Linux | Linux | Linux |
| Built-in Bluetooth | |||
| Built-in Wi-Fi | |||
| USB Headset (Accessory, pruchased separately) | |||
| Camera | |||
| Video Resolution | |||
| Video Codecs | |||
| 3-way Video Conferencing | |||
| 5-way video/audio mixed conferencing | |||
| HDMI |