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Small black square Bluetooth adapter with red and white RCA cables and 3.5mm jack

KAIY C39 Bluetooth Audio Adapter 3.5mm RCA 3D Surround

SKU CH-Z84C-PH3QX

Adds Bluetooth to wired stereos and speakers through 3.5 mm and RCA inputs with a one-touch 3D surround mode

  • ColorBlack
  • Cable Length2.48
  • SpecificationsKAIY
  • Connector BAuxiliary
  • Connector StyleRCA
  • Dimensions2.7 in x 2.7 in x 1.3 in
  • Turns vintage stereos wireless with RCA and 3.5 mm inputs
  • One-touch 3D surround mode widens stereo depth
  • Fits 99% of wired audio gear via dual ports
  • Compact 2.7 × 2.7 × 1.3 in design hides neatly
  • Includes 2.48 in cable for flexible placement

Wireless Upgrade for Wired Audio

The KAIY C39 Bluetooth audio adapter adds wireless streaming to any stereo system that has a 3.5 mm auxiliary input or RCA jacks. It arrives new in black with a 2.48 ft cable and measures 2.7 in by 2.7 in by 1.3 in. The single unit plugs in and pairs with a phone or tablet so vintage hi-fi gear, desktop speakers or a car stereo can play music without cables.

Dual 3.5 mm and RCA Connections

The adapter provides both a 3.5 mm auxiliary port and a pair of RCA connectors, covering 99 percent of wired audio devices according to the manufacturer. This single specification decides whether the C39 matches the inputs on the target equipment. No other interface or wireless protocol is included in the supplied data.

Ideal for Retro and Everyday Systems

Buyers who want to keep a classic receiver or amplifier while adding Bluetooth streaming will find the RCA path a direct fit, and the 3.5 mm jack serves portable speakers or vehicle aux inputs. The adapter does not suit setups that require digital optical, HDMI or multi-room audio, nor does it address needs for app-controlled EQ, battery-powered portable use or high-resolution codec support.

Highlights

  • Turns vintage stereos wireless with RCA and 3.5 mm inputs
  • One-touch 3D surround mode widens stereo depth
  • Fits 99% of wired audio gear via dual ports
  • Compact 2.7 × 2.7 × 1.3 in design hides neatly
  • Includes 2.48 in cable for flexible placement

Specifications

BrandKAIY
ModelC39
ColorBlack
Cable Length2.48
SpecificationsKAIY
Connector BAuxiliary
Connector StyleRCA
Dimensions2.7 in x 2.7 in x 1.3 in
Package Quantity1

Questions about this item

What does the 99% compatibility figure mean when I connect this adapter to my vintage stereo?

It indicates the adapter's dual 3.5mm AUX and RCA interfaces fit the vast majority of wired audio devices, letting you stream wirelessly to old receivers, desktop speakers, or car stereos without replacing them.

Which connection standard does the RCA interface use and what does it limit?

The RCA (red/white) ports provide an analogue line-level connection standard for vintage hi-fi gear; they cap the signal to stereo analogue audio with no digital processing or surround decoding beyond the unit's own 3D mode.

Will the 2.7 in by 2.7 in by 1.3 in body and 2.48 cable length fit behind my equipment rack?

The compact square chassis measures 2.7 inches wide and deep by 1.3 inches high, and the attached cable runs 2.48 units long, so it sits neatly behind most racks or inside a car console.

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