Club-3D USB-C to RJ45 Ethernet 2.5G Adapter (CAC-1520)

Name: Club-3D USB-C to RJ45 Ethernet 2.5G Adapter (CAC-1520)
Brand: Club-3D

Here is a closer look at Club-3D USB-C to RJ45 Ethernet 2.5G Adapter (CAC-1520).

About

A Realtek RTL8156BG 2.5Gbps adapter whose own spec sheet explicitly states the host connection needs double the target Ethernet bandwidth to run reliably — a 5Gbps USB-C port comfortably covers the 2.5Gbps link with margin against bit-error-rate collisions. Bus-powered; requires manual driver installation for Windows 11 and current macOS.

Ports: 1× Ethernet (2.5GBASE-T) and 1× USB-C (host)

Confirmed with

Notebook (generic)
Confirmed as a replacement for the failed native Ethernet port on a Lenovo ThinkPad T495, and separately tested via iperf showing ~2.35 Gbps sustained throughput. Under sustained hours-long 2.5Gbps loads on Debian-based Linux servers, USB bus stabilization can degrade compared to native PCIe.