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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Baseus USB C Hub Type C to HDMI USB HUB Adapter 13-In-1 DP 4K 60Hz 120Hz RJ45 VGA Converter PD 100W USB A 3.1 2.0 For Macbook PC
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
NEW PCIE Gigabit Ethernet Network Card PCI Express X1 to RJ45 Network Adapter 10/100/1000Mbps Network Controller LAN Card for PC
Aliexpress UK
Connect the RJ45 end to the console port of your network device and the DB9 end to your computer's serial port. 1 x RJ45 to DB9 Serial Console Cable. High-Quality Construction: Features a flat design with a 28AWG copper conductor, ensuring durability and stable performance.
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M.2 B+M Single-Port 10GbE Network Card RJ45 Ethernet Network Adapter AQC113 Industrial Control Grade Server Network Card
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
Thunderbolt 2 To FireWire 800 1394B Adapter Thunderbolt 2 To 3 Ethernet rj45 For Mac Computers Equipped With Thunderbolt Ports
Aliexpress UK
330 degree bending, ESD electrostatic protective, support remote wake. Features: Transmission without attenuation and delay, applicable to multiple devices and suitable for multiple systems. Due to the differences between different monitors, the picture may not reflect the actual of the item.
eBay
Up Down Left Right Angle Ethernet Adapter 90 Degree and 270 Degree RJ45 8P8C Ethernet Female To 8P8C Male Adapter
Aliexpress UK
Connector A: DB9 9 Pin Male Connector B: RJ45 8 Pin Female Data cabling transmission signal up to 20M Compatible with Standard 9 Pin D-sub RS-232 Devices e.g. computer laptop, printer, modem, router, PDA, POS device, digital CNC machine tool, Barcode scanner, etc. Please be Noted: DB9 serial RJ45 adapter is only an adapter for extending RS232 serial data (max. distance 65ft), not a console adapter. Usually this adapter needs to be used in pairs. DB9 serial data is transmitted over the network cable. To use this pair of adapters, you need to connect them with a cat5e or CAT6 cable. Whats Included 1x DB9 Male to RJ45 Female Serial Adapter.
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RJ45 1 to 2 Lan Ethernet Network Cable Female Splitter Adapter Connector Dual Adapter Port Coupler Cable Extender
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 Ethernet Adapter 2.5G USB 3.0 Type C to RJ45 Network Card Wired Ethernet Gigabit Adapter Lan Card Hub for MacBook iPad
Aliexpress UK
Item Type:TXI022 RJ45 to RS232 Serial Network Adapter. WIDELY COMPATIBLE: Ethernet RJ45 to RS232 converter supports all for systems, such as for XP, for WIN7, for WIN8, for WIN10. Adapter Type: RJ45 Ethernet to RS232 Serial Port.
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M2 RJ45 Network Adapter RTL8125BG Chip M.2 Gigabit Ethernet Network Card 2.5G/1000/100Mbps Ethernet Adapter Mini PCIE
Aliexpress UK