Black · Relay transmitterTRAVEL TECHTravel Tech
Your headphones. The seatback screen.
Avantree Relay
Black · TC218 · transmitter
Buyer feedback ↓Plug Relay into a headphone jack and send the audio to Bluetooth headphones. It can share the sound with two listeners, with volume buttons and battery lights on the adapter.
- 2 headphonesShared listeningBluetooth audio output
- Up to 25 hoursRated playbackDepends on use and connected headphones
- 3.5 mm inputHeadphone-jack connectionDual-prong airplane adapter included
Amazon US · Black · TC218 · transmitter · Retailer link
THE QUICK TAKE
Is it right for you?
A useful travel extra if you want your own wireless headphones for a seatback movie. Relay handles the wired-to-wireless connection, and the two-headphone option is handy when you want to share one screen.
Skip it if you need a Bluetooth receiver or a microphone connection. Relay only sends audio to headphones. Sound delay also depends on the headphones' codec, so its aptX features do not promise perfect lip sync with every pair of earbuds.
01 / BUYING NOTES
Before you buy.
Avantree Relay specifications and setup ↗ · Qualcomm aptX product listing ↗ · Exact Amazon Relay listing ↗
02 / AMAZON REVIEWS
The buyers’ view.
Owners report convenient wireless seatback listening, including sharing a movie through two pairs of headphones. Pairing experiences are mixed: some find it quick, while others describe a finicky first connection or easier setup after disconnecting headphones from their phones.
Audio reliability also varies. Owners describe stable sound through long flights, but one reports scratchy audio that repeatedly required disconnecting and reconnecting during a flight.
What buyers like
- quality412
- ease of use216
- portability169
- sound quality159
- battery life138
Mixed feedback
- connectivity481
- Value for money141
- latency123
The small numbers are review mentions. Topics and sentiment are from Amazon’s customer-review overview.
Amazon US · Checked . Ratings may include other colors and sizes.
View source ↗03 / REVIEWS & VIDEO
See it in use.
See how it works, then read the findings behind the buying advice.
Avantree Relay tips and setup
See the pairing and control routine for the adapter before a trip.
Watch on YouTube ↗Video and written sources are labeled by creator and tested scope. Manufacturer demonstrations explain use; they are not independent tests. No in-house hands-on testing is claimed.
Read 2 written sources Product scope is labeled · key findings in bold
Avantree confirms two-headphone transmission and identifies Relay as a transmitter only. Its codec table also lists different delays for different audio formats; compatibility and low latency are separate questions.
Qualcomm lists Relay with aptX Adaptive support. That confirms a supported codec, not that every paired headphone can use it.
04 / COMPARE
Different priorities.
Choose the tradeoff that fits how you will use it.
Swipe to see every alternative →
THIS GUIDEAvantree RelayBlack · TC218 · transmitter |  ALTERNATIVETwelve South AirFly ProOriginal white 12-1911 · not Pro 2 | |
|---|---|---|
| Amazon price | $34.99 | $37.99 |
| Best for | Wireless listening from a seatback jack | Travel listening plus a receive mode |
| What changes | Transmitter with two headphone connections | Switch between transmitting and receiving audio |
| Consider | No receive mode or microphone audio | Original model has a different control layout |
| Explore | Read buying guide →Source ↗ | Read buying guide →Source ↗ |
About these everyday comparisons
Approximate comparisons to familiar objects: a bank card’s 3.37-inch long edge, a Letter sheet’s 11-inch long edge, or a US nickel’s 21.21 mm diameter / 5 g weight. Water comparisons exclude the container’s weight. Capacity comparisons describe volume, not exterior size or how food fits. Reference pictures identify the object; use the labeled ratio for the comparison.
05 / PRICE HISTORY
The price over time.
Avantree Relay · Black · TC218 · transmitter · Amazon US
The chart legend identifies Amazon and new-offer prices when available. New offers can include marketplace sellers. Coupons, shipping and size/color selections can change the final price. Blank periods are missing observations, not a zero price.
06 / RELATED FINDS
A useful extra.
For the way you plan to use it.
Add noise cancellation for the trip.
Sony WH-1000XM4
A folding over-ear pair gives Relay a wireless listening partner while reducing background cabin noise.