1. RS485 communication interface: A+, B- are connected to the 485+, 485- interfaces of the inverter respectively 2. DC8-36VKF128 terminal power supply port: 8-36V, GND are connected to the 24V, GND interfaces of the inverter respectively 3. SIM card slot: supports the installation of IoT traffic cards or ordinary mobile phone cards, supports full network access, the metal side of the card is facing down during installation and pay attention to the direction of the card 4. Type-C USB 5V power supply interface: KF128 terminal power supply and USB power supply can be either 5. antenna interface: It is recommended to use an antenna with a gain of about 5DBI SMA antenna interface: You can choose either or SMA antenna. SMA antenna is suitable for occasions where an external antenna is required. It is recommended to use an antenna with a gain of about 8DBI Color: As shown Material: plastic Package Contents: 1 x frequency converter board Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.