1 x RJ9 4P4C male to female adapter cable. Interface: RJ9 male to RJ9 female. Very suitable for all phone models that often turn off the headset, and can be used with all directly connected headset models.
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Wire Connector Universal Compact 2 Pin Splicing Terminal Blocks Led Lighting Electrical Quick Connectors Guide Rail Connector
Aliexpress UK
Features: Professional H132R Call Center headsets with two Mode Noise Cancellation (20-40dB reductions) and Universal RJ9/QD connectors for Clear Communication. The length of the headphone cable: about 2M.
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Tank Connector Bulkhead Tank Connector Bulkhead Fittings Hose Bulkhead Connector For Rain Barrels, Aquariums, Water Tanks
Aliexpress UK
Interface: RJ9 male to dual female ports. Size: line length 50cm.
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200/1Pcs Double Wire Plug-in Connectors 2 Pin Way Plug Electric Wire Snap Connector Waterproof Quick Connector Cable Clamps Snap
Aliexpress UK
Interface: RJ9 male to dual female ports. Size: line length 50cm.
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SP21 waterproof connector 2/3/4/5/6/7/8/9/10/12 pin 21mm Panel mount connector male and female connectors ,IP68
Aliexpress UK
Connector Type: 4P4C. 50 x RJ9 Connector. Transparent color. Net Weight: 33g.
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2/10pcs BNC Female Connector to BNC Female Coupler Adapter plug Connector Female Connector for CCTV ip Camera E3
Aliexpress UK
Interface: RJ9 male to dual female ports. Size: line length 50cm.
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50/1pcs T Type 2 Pins Wire Splice Connectors Push-in Lever Quick Wire Connectors Wire Connectors
Aliexpress UK
Interface: RJ9 male to dual female ports. Size: line length 50cm.
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20/30/40 Pieces Lever Wire Connector for Quick Connection 28-12 Awg 1 Pair 1 Direct Plug Wire Connector Compact Connector
Aliexpress UK
Interface: RJ9 male to dual female ports. Size: line length 50cm.
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5Pcs COB LED Strip Connector 2/3/4pin 5/8/10mm Corner Connectors for COB LED Strip 5V 12V 24V Welding-free Quick Connectors
Aliexpress UK