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Small black Bluetooth transmitter with 3.5mm jack and volume buttons

SuperTooth Relay BTTC-218 Bluetooth Transmitter 25Hrs 3.5mm

SKU CH-4MT7-EVNV3

Connects wireless headphones to 3.5mm audio sources such as airplane seat screens with Qualcomm aptX Adaptive and up to 25 hours battery life

  • Talk durationUp to 15 hour(s)
  • Music playtimeUp to 15 hour(s)
  • Standby durationLithium-Polymer
  • Charging time2 h
  • Bluetooth profileAVRCP
  • Battery packLithium-Polymer
  • Connects to airplane seat screens via 3.5mm jack
  • Qualcomm chip with aptX Adaptive and HD audio
  • Pairs two Bluetooth headphones for shared listening
  • Firmware-upgradeable for ongoing compatibility improvements
  • Up to 25 hours battery with built-in volume controls

Airplane Seat Audio Adapter

The SuperTooth Relay BTTC-218 connects to aircraft seatback screens through a standard 3.5mm AUX jack. It streams in-flight entertainment wirelessly to your own Bluetooth headphones such as AirPods or Bose models. The device is built specifically for travel scenarios and is not compatible with TVs, phones, tablets, hearing aids or musical instruments. It functions as a transmitter only and cannot receive audio from other sources.

Dual Link And Firmware Updates

The adapter supports simultaneous pairing of two Bluetooth headphones so two listeners can share the same audio source. A supplied dual 3.5mm plug adapter ensures compatibility with both single and twin-jack airline sockets. Firmware can be upgraded to improve AirPods compatibility, dual-device stability and overall performance over time. The Qualcomm chip enables aptX Adaptive and aptX HD audio codecs for clearer wireless sound.

Simple Setup With Long Battery

Pairing is handled through intuitive LED indicators that guide you through single or dual device connections. Built-in volume controls and a clear battery indicator let you adjust levels without touching the seat screen. The lithium-polymer battery delivers up to 25 hours of playtime and recharges fully in 2 hours. The transmitter-only design means it will not pair with phones or tablets, avoiding accidental connections.

How it compares

Measured against everything we stock in Bluetooth Earbuds & Headsets, at today’s prices. Recalculated every night.

Price $37.99
Pricier than about 60% of the 870 comparable items (median $30.99).

Specifications

Product
Brand nameSuperTooth
Product lineRelay
Model nameBTTC-218
Part numberBTTC-218
Product colorBlack
Connectivity
Bluetooth profileAVRCP
Power
Talk durationUp to 15 hour(s)
Music playtimeUp to 15 hour(s)
Standby durationLithium-Polymer
Charging time2 h
Battery packLithium-Polymer

Questions about this item

How long before the built-in battery needs recharging on a long flight?

The internal lithium-polymer cell delivers up to 25 hours of playtime and recharges in two hours via USB-C.

What connection limit appears first when streaming to two headsets continuously?

Dual Link supports two Bluetooth headphones simultaneously; a third device cannot be added.

Does the adapter get warm or noisy during a full-day journey?

Solid-state design means no fan noise and negligible heat during extended use.

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