These are four power units for security cameras with 12-volt batteries. In case of a power outage, the cameras will continue to operate. However, be cautious, the box is exposed to the sun, so it should be placed in a cool place. As for the small device, this device opens the parking gate for car entrances. It works on a USB system. When you place the USB input inside the car 🚗, when you approach the parking, the gates will open for you 👍. The price for this part is 100 riyals. The power units with batteries are 600 riyals for the four 👍🙏