USB4 to Dual 25G SFP28 Network Adapter

About this product

This product is a plug-and-play external network adapter that adds dual-port 25G fiber optic connectivity to your computer (Mac, Windows PC, or Linux computer) via a USB4/Thunderbolt port. With its compact design and quiet operation, it is ideal for high-speed networking applications such as video post-production, data centers, and large-file transfers. Lekuo DTB3F25: USB4 to Dual-Port 25G SFP28 Fiber Network Adapter

Q&A Q: What main controller chip does the DTB3F25 NIC use? A: This NIC adopts a high-performance Mellanox chip, ensuring enterprise-grade stability, ultra-low latency, and excellent high-speed data transfer compatibility. Q: Is this USB4 NIC compatible with Thunderbolt 3, Thunderbolt 4, or Thunderbolt 5 ports? A: Yes. Its upstream USB4 40Gbps interface is fully backward and forward compatible with Thunderbolt 3, Thunderbolt 4, and Thunderbolt 5 ports. Q: Does the DTB3F25 require a driver installation on Mac OS? A: No. It is completely driver-free (plug-and-play) on Mac OS, allowing Apple users to directly enjoy 25G high-speed networking after connection. Q: What is the actual file transfer speed of this 25G NIC over the internal network? A: In an internal network environment, its actual transfer speed can reach approximately 2.75 GB/s, which nearly saturates the practical bandwidth limit of the 40Gbps USB4/Thunderbolt channel. Q: Does the downstream USB4 port support daisy-chaining and device charging? A: Yes. The downstream USB4 40Gbps port supports 60W PD charging output and daisy-chaining, allowing you to connect additional displays, storage devices, or docking stations. Q: Can this NIC be used with a 10G SFP+ fiber module? A: Yes. The dual SFP28 ports support 25Gb/s and 10Gb/s auto-negotiation, so they are compatible with 25G SFP28 modules as well as 10G SFP+ modules or DAC direct-attach cables. Q: Does this NIC support Jumbo Frames to accelerate large file transfers? A: Yes. It supports Jumbo Frames up to 9000 bytes (9K) Mac 2K, which can significantly reduce CPU usage during video post-production or large data transfers. Q: Does this NIC require an external power supply? A: Yes. Due to the high-performance operation of the dual 25G ports and the downstream 60W PD output requirement, this product must be connected to the included external DC power adapter to ensure stable operation. Q: Which operating systems does the DTB3F25 support? A: It widely supports Mac OS (driver-free), Windows 11/10, and Linux systems, suitable for various workstations, laptops, and server environments. Q: What do the LED indicators on the SFP28 ports represent? A: Solid yellow indicates successful 25G link, blinking yellow indicates data transfer in progress, and off means no network connection.