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Small square Bluetooth 4.2 adapter with 3.5mm jack and micro USB port

Ruth's sister

Ruth's sister KN319 Bluetooth 4.2 2-in-1 audio adapter

SKU CH-A9RY-0GAKQ

A 2-in-1 Bluetooth 4.2 transmitter and receiver with 3.5 mm aux, RCA and micro-USB cables included, running up to 6 hours per charge within a 10 m range

  • Bluetooth 4.2 streams audio up to 10 metres away
  • Switch between receiver and transmitter modes instantly
  • Built-in 200 mAh battery lasts 6 hours receiving
  • Includes 3.5 mm aux, RCA and micro-USB cables
  • Pocket-sized 44 × 44 × 12 mm design weighs 18 g

2-in-1 Bluetooth 4.2 audio adapter

The Ruth's sister KN319 works as both a transmitter and a receiver using Bluetooth 4.2. It connects to devices through a 3.5mm auxiliary jack and includes RCA and micro USB cables. A built-in 200mAh lithium-polymer battery provides up to 6 hours of use in receiver mode and 5 hours in transmitter mode.

Adds Bluetooth to wired speakers or headphones

Ideal for streaming audio from a phone to a legacy sound system or for sending TV sound to wireless headphones. The adapter pairs as BT-01 in receiver mode and operates within a 10 metre range when unobstructed. Not suited for users who need aptX or AAC codec support or who require longer battery life for all-day listening.

Bluetooth 4.2 with 3.5mm interface

The single specification that decides compatibility is the Bluetooth 4.2 standard combined with a 3.5mm audio connection. This determines which source devices can pair and which playback equipment can be used without extra converters.

Highlights

  • Bluetooth 4.2 streams audio up to 10 metres away
  • Switch between receiver and transmitter modes instantly
  • Built-in 200 mAh battery lasts 6 hours receiving
  • Includes 3.5 mm aux, RCA and micro-USB cables
  • Pocket-sized 44 × 44 × 12 mm design weighs 18 g

Specifications

No published specifications for this item yet.

Questions about this item

How do I switch the KN319 adapter between receiver and transmitter modes during installation?

Slide the side switch to TX for transmitter or RX for receiver, then pair using the 3.5 mm aux or RCA cable; the step users often miss is setting the mode before powering on.

What battery maintenance will the KN319 need after repeated charge cycles?

The built-in 200 mAh Li-Polymer cell is not user-replaceable; when run-time drops well below 6 hours in receiver mode or 5 hours in transmitter mode, the whole adapter must be replaced.

What range limit appears first when using the KN319 continuously in a typical room?

The Bluetooth 4.2 link is rated for 10 m or 33 ft line-of-sight; walls and interference usually cut the reliable distance to roughly half that during sustained streaming.

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