Internal Antenna 2 * GPIO 1 * RS232 / RS485 (Switchable) 2 * Analog Input 2 * 3.3V Output 2 * 5/9/12V Output Switchable 1 * SDI-12 1 * Micro SIM-3FF (For NB-IoT / Cat.M Version) Store Historical Records Locally and Support Retransmission to Prevent Data Loss Power Supply: 2 * 2550mAh Chargeable Batteries Solar Powered (6V, 1.7 W) 5-24VDC IP67 Rated LoRaWAN® Version Only: Supports Multicast for Control in Bulk Ultra-wide-distance Wireless Transmission up to Line of Sight of 15 km NB-IoT / Cat.M Version Only: Support Cumulative Number Report Function for Power Saving NB IoT