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 Pcie to RJ45 Network Card Realtek 8126 100Mbps/1G/2.5G/5G 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
Vention RJ45 Splitter 1 to 2 RJ45 Splitter Network Adapter Female Network Extender Extension Connector for Laptop Ethernet 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
CNLINKO M24 RJ45 Waterproof Connector LP24 Internet Network TV BOX 8P8C Connector CAT3 CAT6 IP68 RJ45 Adapter Plug and Socket
Aliexpress UK
Item contains:One item.
eBay
VGA Extender over Ethernet Cat5e/6 cable 20M VGA to Rj45 Adapter HD VGA 15 Pin Male to LAN RJ45 Female Network Cable Extender
Aliexpress UK
Connector A: Serial (RS-232) Female / DB9 Female (9 Pin). Connector B: RJ45 Female. Excellent : This item is in near-perfect working order. Good : This item is fully functional but shows noticeable signs of wear such as scratches, scuffs, or slight dents.
eBay
Intel I226-V PCIE To RJ45 Network Adapter 2.5G Gigabit Ethernet 100/1000/2500Mbps RJ45 LAN Controller For Desktop/PC Easy Set
Aliexpress UK
Connection: DB9 (RS232) Female to RJ45 female Console adapter for TCP/IP network interface with the doual-way conversion, with the serial port network function, support serial data and network data bi-directional transparent transmission. Compatibility: Compatible with Standard 9 Pin D-sub RS-232 Devices, such as computer, laptop, printer, modem, router, PDA, POS device, digital CNC machine tool, Barcode scanner, etc. 65.6FT: Connect the equipment serial port to the RJ45 console port on routers, support maximum distance 65.6FT. Helpful: Nick-plated and Oxygen-free copper transmission port on the port minimize crosstalk, suppress noise, and protect against electromagnetic interference (EMI) and radio frequency interference (RFI),Premium adapter engineer.
eBay
360° Rotatable Network Plug RJ45 Gigabit Adapter 90 Degrees Right Angle Elbow Universal Connector Male to Female Converter rj45
Aliexpress UK
1 X USB to RJ45 Cable. Wire: UL20251 bare copper 28AWG 8C OD2.5 8.5MM UL standard wire.
eBay
UGREEN RJ45 Splitter 1 to 2 Ethernet Adapter Internet Network Cable Extender RJ45 Connector Coupler for PC Laptop TV Box Router
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
RJ45 To Screw Terminal Adaptor Rj45 Female To 8 Pin Connector For CCTV DVR
Aliexpress UK