We take cryptocurrency — so the coins you hold can buy real hardware.Pay in crypto, spend it on real hardware. Free insured shipping worldwide over $399. Plain, unbranded boxes, sent from Germany.Free insured shipping over $399. Your rate is locked for 30 minutes once checkout opens.Rate locked 30 minutes. Every item sealed, serial-checked and covered by a 24-month warranty.Sealed, 24-month warranty.

Saved items Sign in
Two white in-ear buds and matching charging case on a plain surface

Sennheiser

Sennheiser CX400TW1 White in-ear headphones

SKU CH-V1HN-4S90A MPN CX400TW1 White

True wireless in-ear headphones with 7 mm dynamic drivers, Bluetooth 5.1, aptX support and up to 20 hours total playtime

  • Driver size7 mm dynamic driver
  • Frequency range5 Hz-21 kHz
  • Headphone style<0.08% (1 kHz / 94 dB)
  • Power supplyUSB charging via USB-C socket at charging case
  • Audio sensitivity107 dB SPL (1 kHz / 1 mW)
  • Wearing styleEar canal
  • Superior sound from 7mm dynamic drivers with built-in equalizer
  • Up to 20 hours total playtime with charging case
  • Bluetooth 5.1 with SBC, AAC and aptX codec support
  • Customisable touch controls for music, calls and voice assistant
  • 5 hour full charge, 10 minutes gives 1 hour playtime

True Wireless In-Ear Headphones

The Sennheiser CX 400BT True Wireless are Bluetooth 5.1 in-ear headphones built for listeners who want high-fidelity audio without cables. They use 7mm dynamic drivers and support SBC, AAC and aptX codecs for broad device compatibility.

Charging Case and Touch Controls

Each earbud weighs 6g and the white charging case weighs 37g, holding a 420mAh battery that extends total playtime to 20 hours. A USB-C socket on the case provides a full charge in 1.5 hours, while ten minutes of charging adds one hour of listening. Customisable touch surfaces handle music, calls and voice assistant commands.

Compatibility and Fit Check

Verify that your source device supports Bluetooth 5.1 and at least one of the listed codecs for best performance. The ear-canal coupling relies on a secure seal, so buyers who cannot achieve a comfortable fit with in-ear designs should consider a different form factor.

How it compares

Measured against everything we stock in Earbuds & Over-Ear Headphones, at today’s prices. Recalculated every night.

Price $155.99
Pricier than about 90% of the 7,078 comparable items (median $25.99).

Specifications

Product
Brand nameSennheiser
Product lineCX 400BT True Wireless
Model nameCX400TW1 White
Part number508901
Product typeIn-Ear
Product colorWhite
Audio & video
Driver size7 mm dynamic driver
Frequency range5 Hz-21 kHz
Headphone style<0.08% (1 kHz / 94 dB)
Audio sensitivity107 dB SPL (1 kHz / 1 mW)
Wearing styleEar canal
Mic frequency response100 Hz-10 kHz
Connectivity
Wireless technologyBluetooth 5.1
Profiles: A2DP, AVRCP, HSP, HFP
Codecs: SBC, AAC, aptX
Ports & slots
ConnectionYes
Power
Power supplyUSB charging via USB-C socket at charging case
Run timeUp to 7 hrs music playtime with earbuds
Up to 20 hrs music playtime with charging case
Size & build
Product weight6g (single earbud) / 37g (charging case)
Shipping weight0.20 kg
Package size168 × 112 × 46 mm
In the box
In the boxCX 400BT True Wireless 2 earbuds
Charging case
USB-C charging cable
Silicone ear adapter sets (in size XS/S/M/L)

Questions about this item

What Bluetooth version does the CX400TW1 use, and what codecs are supported?

The earbuds use Bluetooth 5.1 and support SBC, AAC and aptX codecs for wide device compatibility.

What are the dimensions and weight of the charging case?

The charging case weighs 37g and houses a 420 mAh battery; individual earbuds weigh 6g each.

How do I pair the earbuds for the first time, and what step is often missed?

Remove both earbuds from the case to enter pairing mode automatically, then select "CX 400BT" in your device's Bluetooth menu.

More in Earbuds & Over-Ear Headphones

Similar items