IEEE802.3af compliant. Support PoE applications in both of Fast / Gigabit Ethernet environments. Support wide input voltage range 37Vdc to 57Vdc. Thermal cut off. Short circuit protection. Over current protection Programmable Classification (Default:Class 0). High DC/DC converting efficiency. Less external component one output decoupling capacitor. Isolation level 1.5KVrms.Enhanced surge protection. Internal build in 2 channel bridge rectifiers. Material: PCB colour: Black The production time is different, and the batch number below PM0503T is different, which does not affect the use Package Contents: 5 x POE Module Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.