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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5Gbps PCI-E To RJ45 Network Card Realtek8126 1G/2.5G/5G RJ45 Interface Gigabit Ethernet PCI Express Wlan Adapter For PC Win10/11
Aliexpress UK
1 9PIN Adapter. RJ45 Pin Outs: 1-Blue, 2-Orange, 3-Black, 4-Red, 5-Green, 6-Yellow, 7-Brown, and 8-White. It reduces signal loss and interference. Used for module RS232. Make customized serial connections.
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1pc RJ45 Feedthrough Coupler,STP RJ45 CAT6 Network Female Straight Coupler Converter Ethernet Extension 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
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
Startech.com Serial Adapter RJ45 Female to RJ45 Male.
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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 RJ45 Female Socket to 9 pin Serial DB9 Socket Adapter allows you to connect devices with an Ethernet (RJ-45) female port to devices with a serial (RS-232) female port.. The adapter is compatible with various brands and models, it provides a 1:1 connection split/duplication for your networking needs.
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CAT5E RJ45 Male to Terminal Block cable, Solderless RJ45 to 8 pin terminal block adapters with 20cm Pigtail Cable
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
Professional UTP/STP RJ45 CAT5E/CAT6.A Ethernet Cable,RJ45 LAN Network Adapter Ethercon Extension Cord for LED Stage
Aliexpress UK
UART Interface: 1 RS232, 1 RS485 RS422 Composite Port. Item Type: RS232 RS485 Serial to Ethernet Adapter. 1 x RS232 RS485 Serial to Ethernet Adapter. POWERFUL INDICATOR FUNCTION: With power, Link/act, TX, RX and RS232 five indicators, can intuitively display the working status of the device.
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For NZXT Aer RGB 2 Light In Out Serial Cables Input Cable Connection Case Fan Adapter Cable
Aliexpress UK