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Tycon Mid Span. 1A per port. Gigabit PoE Injector. 4 ports with 1-4 power sources
Intellinet 4-Port Gigabit Ultra PoE Extender (561617) – Intellinet Europe
Amazon.com: PoE Ethernet Power Supply 4 Port POE DC 12V-48V Power Adapter Injector for IP Camera 802.3af/802.3at Device : Electronics