It's just like a normal network switch (dumb router), but it also has PoE+ (30W Power Over Ethernet), which allows you to power up to four 30W 4 security cameras with lights, plus more using a Gigabit PoE extender. It comes with one 2-port Gigabit PoE extender, which allows you to add another security camera without drilling another hole, or use it as a ethernet switch that doesn't need a power supply. Reolink sells a really good PoE doorbell camera.
If you just want to add PoE to your existing Wifi router, I also have a 30W Gigabit PoE power injector with a 2-port gigabit PoE expander for $20, and I have two 15W PoE 10/100 POE injectors for $5 each.
I can set your cameras up for you for $25 per hour. I also have some 4K Reolink RLC-810 PoE security cameras for $50 each.