Net Optics 10/100/1000 Port Aggregator Tap IPA-CU3 copper RJ-45 ports. I've used this in my lab. This is a 10/100/1000 network tap, but for some reason I cannot get the tap to negotiate or set at 1000 mbps. You might be able to get it to run in this mode, but for whatever reason I've been having issues. 

As you can see in the picture with the laptops, I tested the tap to ensure it provided passthrough and copied traffic. 

I connected two laptops together through the tap and ran iperf3. The third laptop connected to one of the output tap ports (port A) and displayed captured traffic on Wireshark.

This is perfect for a lab where you want to tap rather than span to get traffic.

The power supply is included.

The network management interface works, as does the RS-232 port. To connect to the RS-232 port, use 

19200 baud
8 data bits
No parity
1 stop bit
No flow control

I connected via Linux using the cu terminal and logged in with username netoptics password netoptics.

Thank you for looking.