| Audio | Proprietary 3.5mm for PTT, compatible with some non-PTT 3.5mm headsets | Proprietary SecureAudio Connector, compatible with some 3.5mm accessories with Sonim adapter | Proprietary SecureAudio Connector, compatible with some 3.5mm accessories with Sonim adapter |
| USB-C | USB 2.0, unable to be used for audio and power at the same time, not compatible with 3.5mm adapters. | USB 2.0, unable to be used for audio and power at the same time, not compatible with 3.5mm adapters. | USB 3.1 |
| Compatible with USB-C accessories, with the ability to create custom accessories that screw into the handset for an ultra-reliable connection | Compatible with USB-C accessories, with the ability to create custom accessories that screw into the handset for an ultra-reliable connection | Compatible with USB-C accessories, with the ability to create custom accessories that screw into the handset for an ultra-reliable connection |
| Charging Pins | Yes | Yes | Yes |
| XPand | No | Yes, proprietary XPand connector | Yes, proprietary XPand connector |
