9 Pin (DB9) Serial "Y" Splitter Male - Female - Female Cable
Shop | StarTech.com 16in 9 Pin Serial Male to 10 Pin Motherboard Header Panel Mount Cable - motherboard to RS232 (PNL9M16) - serial cable - DB-9 to 10 pin IDC - 1.3 ft
RS232 DB9 9 Pin Female To TRS 2.5mm Male Stereo Serial Data Converter Cable 6Ft | eBay
6 Foot DB25 25 Pin Serial Port Null Modem Cable Male / Female RS232
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StarTech DB9 RS232 Serial Male to Male Null Modem Adapter NM9MM
10M 30FT 9 Pin Serial Null Modem Cable Cross Female to Female RS232 DB9 F-F | eBay