AXIS 90 W Midspan AC/DC is for installations where mains power is not an option. With a power input of either 24 V AC or 20-26.4 V DC, it can deliver up to IEEE 802.3bt (90 W) to the network device. 24 V AC can be needed in harsh environments where new cabling or installations are not an option and you need to retrofit box, dome or PTZ cameras. 20-26.4 V DC can be used where battery back-up is needed or for solar-powered installations. Or when the network device is built in another equipment and is powered directly from it.