CRS112-8P-4S-IN is an eight Gigabit RJ45 port PoE switch, that offers different power output options: autosensing 802.3af/at PoE/PoE+ and Passive PoE, and four SFP ports provide optical fiber connectivity options to support uplinks of up to 1 Gbps.CRS112-8P-4S-IN is equipped with 12 independent switching ports. 28 V 3.4 A power supply is already included in the box. There is secondary DC jack on the back of the enclosure that supports 48-57 V power supply (not included, can be purchased separately). CRS112-8P-4S-IN can power 802.3af/at devices if 48-57 V DC input is used (unit will automatically detect and provide correct power to devices). Max current is 1 A per port if input voltage is 18-28 V, 450 mA if 48-57 V. Total limit is 2.8A@24V and 1.4A@48-57V. PoE-Out is passed over mode B 4,5 (+) and 7,8 (-) pins