This is a BT Synergy 4500 Adaptor, which is compatible with the 4500 model. It has a single-mode fibre type and comes in the colour black. The adaptor features a powered unit and has a connector A of an unknown type, while connector B has only one. The cable length and output voltage are both unknown. This unit is suitable for use with mobile phones and home phones, and falls under the category of cords, cables, and adapters.
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