Compatible Plug Standard and Bi-directional Adapter: converts either OMTP to CTIA or CTIA to OMT. Universal 3.5mm OMTP to CTIA Male to Female Earphone Converter Adapter Cable. 1 Piece 3.5mm Adapter.
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For Nintendo Adapter EU Plug Charger Power Adapter For All Nintendo 3DS 2DS NDSi Consoles Charging Cable Travel Charging Adapter
Aliexpress UK
Can be universally converted. Compatible : OMPT to CTIA or CTIA to OMTP. colour: black. Item Type: Adapter. 3 x Adapter.
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EU Plug Adapter CN US To EU Travel Adapter Mexico China Japan American To European Euro Converter Adapter Wall Electric Socket
Aliexpress UK
Compatible Plug Standard and Bi-directional Adapter: converts either OMTP to CTIA or CTIA to OMT. Universal 3.5mm OMTP to CTIA Male to Female Earphone Converter Adapter Cable. 1 Piece 3.5mm Adapter.
eBay
2 Europe to US, Italy, Switzerland, South Africa travel adapter plugs, 2-pin wall socket adapter, travel-friendly power adapter
Aliexpress UK
Compatible Plug Standard and Bi-directional Adapter: converts either OMTP to CTIA or CTIA to OMT. Universal 3.5mm OMTP to CTIA Male to Female Earphone Converter Adapter Cable. Compact size and light weight, gold plated connector allows for better signal connection.
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1PCS M.2 to USB Adapter B Key M.2 SSD Adapter USB 3.0 No Cable Needed USB to 2280 M2 SSD Drive Adapter NGFF Converter SSD Reader
Aliexpress UK
2 pcs OMTP to CTIA / CTIA to OMTP Headset Audio Adapter 3.5mm Earphone Converter Features: Colour: black Connection type: 3.5mm Brand compatible: omtp to ctia or ctia to omtp Length: 4.3 cm (approx.) Durable, compact, and lightweight Gold plated 3.5mm to 3.5mm stereo adapter Gold-plated to ensure the best quality of sound Quantity: 2 pcs Package includes: 2 x Ctia to omtp converter adapter
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Ugreen USB 2.0 Printer Adapter USB Type c Adapter For Printer Hard Drive Base Fax Machine Scanner USB 2.0 Type c Printer Adapter
Aliexpress UK
Also there are vairious OMTP type based on Device Temperature to oprate. so it may not support enitire OMTP Family. however it will support most convertor. OMTP Type Male 3.5 MM Connectors to CTIA 3.5 MM Type Connectors Convertor.
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AS Adapter Cable SAS To SATA 29 Pin Famale 4 Pin Male Cable Connector Adapter Converter For Hard Disk Drive Power Cable Adapter
Aliexpress UK
Can be universally converted. Compatible : OMPT to CTIA or CTIA to OMTP. colour: black. Item Type: Adapter. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing.
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2 in1 Adapter Type C OTG Adapter USB-C Male To USB 2.0 Female Adapter For Macbook Xiaomi HUAWEI Samsung OTG Connector
Aliexpress UK
Can be universally converted. Compatible : OMPT to CTIA or CTIA to OMTP. colour: black. Item Type: Adapter. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing.
eBay
Olaf USB Type C To 3.5mm Jack Headphone Adapter USB A/USB C To 3.5mm Audio Adapter Cable Built in DAC Aux Adapter For PC Laptop
Aliexpress UK