Scollar Trek is designed for active dogs. It includes GPS, highly tuned antennas, Cat M1 cellular, Bluetooth BLE, 900 MHz RF, motion sensors, LED lighting, microphone, speaker and a rechargeable battery system with two batteries and a charging base, ensuring you will always have one fully charged battery ready to go. The RF can be used to open pet doors. Two module ports enable expanded functionality for invisible fences, perimeter barriers and anti-bark. The device is waterproof to IP68 standard and fully integrated with the Scollar app and cloud service to keep you up to date on your pet. No additional monthly fees are required for tracking. Choose standard Scollar Trek or Scollar Mini, designed for cats and toy dogs.