This modular adapter has a DB9 female connector that plugs into DB9 RS232 serial port and converts it to an RJ45 connection. These modular adapters convert from a DB9 to an RJ45 socket jack (female).
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5G PCI-E to RJ45 Network Card Realtek 8126 1000/2500/5000Mbps RJ45 Interface Gigabit Ethernet PCI Express X1 X4 X8 X16 Adapter
Aliexpress UK
This modular adapter has a DB9 female connector that plugs into DB9 RS232 serial port and converts it to an RJ45 connection. These modular adapters convert from a DB9 to an RJ45 socket jack (female).
eBay
4K HDMI-compatible Extender RJ45 Ports Up to 30m Over CAT6 5E Network Ethernet LAN TX RX Adapter Cable HDTV to RJ45 for DVD PS4
Aliexpress UK
Model: US013. Interface Type: USB to RJ45. Item Type: Adapter Cable. Colour: Black. 1 x Adapter Cable. Cable Length: Approx. 1.5m / 1.6yd. Support System: For /OS X / System.
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Rj45 Splitter 1 to 2 Gigabit Ethernet Adapter Internet Network Cable Extender Rj45 Connector for PC TV Box Router Sharer
Aliexpress UK
This modular adapter has a DB9 female connector that plugs into DB9 RS232 serial port and converts it to an RJ45 connection. These modular adapters convert from a DB9 to an RJ45 socket jack (female).
eBay
CAT5E RJ45 Male to Terminal Block cable, Solderless RJ45 to 8 pin terminal block adapters with 20cm Pigtail Cable
Aliexpress UK
The HP DB 9Pin RS232 Serial To RJ45 CAT5 Ethernet Adapter LAN Console Cable is a high-quality cable designed for connecting a serial device to an RJ45 Ethernet port. With a cable length of 1.5m, this versatile adapter features a female serial connector on one end and a male RJ45 connector on the other, allowing for easy conversion between the two types of connections.
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Professional UTP/STP RJ45 CAT5E/CAT6.A Ethernet Cable,RJ45 LAN Network Adapter Ethercon Extension Cord for LED Stage
Aliexpress UK
This is NetApp part number 112-00054, a serial to Ethernet RJ45 cable, allowing access to the console of a compatible NetApp controller.
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Vention Cat7 Ethernet Extension Cable RJ45 Cat7/Cat6 Male to Female Rj45 Ethernet Extender Adapter for PC Laptop Ethernet Cable
Aliexpress UK
Built-in CH340 chip, as long as you can connect to the Internet, it will automatically install the driver. Type: USB2.0 RS232 to RJ45. USB serial cable, USB to serial cable, USB CONSOLE cable. 1 Adapter conversion cable.
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3 In 1 RJ45 Splitter LAN Ethernet Network RJ45 Connector Extender Adapter Cable for Networking Extension 1 Male To 2/3 Female
Aliexpress UK
This modular adapter has a DB9 female connector that plugs into DB9 RS232 serial port and converts it to an RJ45 connection. These modular adapters convert from a DB9 to an RJ45 socket jack (female).
eBay
2500Mbps PCI-E To RJ45 Network Card I226 Chip Gigabit Ethernet 100/1000/2500Mbps RJ45 LAN PCIe Adapter For Laptop PC Win 10/11
Aliexpress UK