Feature: 1. RS232 to GPRS server support custom registration package and heartbeat package 2. This serial port server support SMS configuration parameters and restart, very convenient 3. The product support for Ali IOT / MQTT, realize remote configuration parameters 4. Come with various tools to facilitate your installation, simple to start and easy to use 5. Industrial connector come with stable structure, excellent performance and long service life Specification: Item Type: RS232 to GPRS Server Core Parameters: Model Name: HF7311 Function Explanation: Serial port to GPRS Processor: RDA8955 Main Frequency: 256MHz Operating System: For SRX FLASH Resources: 4MB RAM: 4MB Network Interface Parameters: Cellular Standard: GSM/GPRS Antenna Form: External SMA male Cellular Frequency Band: 850/900/1800/1900MHz Cellular Communication Network Protocol: TCP, UDP, DNS Cellular Transmit Power: GSM850/GSM900: Class 4 (2W) DCS1800/PCS1900: Class 1 (1W) GPRS Rate: Downlink 107Kbps, uplink 85.6Kbps Maximum Number of Connections: 3 socket SIM Card Interface: 1.8V/3V (external) Serial Port Interface Parameters: Number of Serial Ports: 1 Interface Standard: RS232 Baud Rate: 1200-460800bps Product Features: Configuration Method: Serial AT command, for IOTService serial configuration software, for IOTService network configuration software WEB Page: Not supported IP Acquisition Method: DHCP Virtual Data Channel: Support Firmware Upgrade: Serial port or OTA upgrade Registration Package Function: Support Heartbeat Package Function: Support Custom Script Function: Not supported Packet Filtering: Not supported Serial Port Automatic Framing: Not supported RTU to TCP: Support NTP Function + Time Zone Setting: Support Parameter Import and Export: Support Reload Reset Interface: Yes Environmental Parameters: Working Temperature: -25-75℃ Storage Environment: -50-90℃, 5-95%RH (non-condensing water) Power Parameters: Input Voltage: 5-36VDC at 1A Interface Form: RJ45 interfaceSize: Approx. 61 x 26 x 18mm / 2.4 x 1 x 0.7in. Package List: 1 x Serial Server1 x GPRS Antenna1 x Crystal Head Turn Button + 4pin Terminal Line1 x Fix Bracket1 x Rail Bracket2 x Screw