Quick overview from the supplier:
Ubiquiti POE Injector U-POE-AF, 802.3af, 48 Volt 0.32A
// Manage Your Networks from a Single Control Plane
Intuitive and Robust Configuration, Control and Monitoring
Remote Firmware Upgrade
Users and Guests
Guest Portal/Hotspot Support
MicroSD
Introducing the UniFi Cloud Key, a miniaturized marvel of technology.
The UniFi Cloud Key is an integrated computer and software controller minus the bulk. It features a quad-core processor with 2 GB RAM, operating the latest version of the UniFi Controller with built-in hybrid cloud technology.