I’ve been using Kiwi Design’s products since October 2023, and they’ve completely transformed my entire virtual reality experience. Most recently, I had the chance to test the new Kiwi Design K4 Duo for the Meta Quest 3. Right from the start, it was clear this was another product they had put serious thought into. As one of the official testers before its release, I was genuinely blown away by the audio quality during my first session. I was asked to try out a variety of games and music to assess their performance across the board.
I started with trying a more intense game, so I jumped into The Walking Dead: Saints & Sinners, and the spatial audio took the immersion to a whole new level. I could hear exactly where the walkers were coming from, even behind me, which added a real sense of paranoia. Then I switched over to testing how it functioned regarding listening to music, and once again, the K4 Duo delivered. It wasn’t overly loud, but I could feel the music deeply. I listened to different genres and artists, including my all-time favourite, Juice WRLD. The experience was genuinely unforgettable.
The setup process for the K4 Duo is quick and hassle-free, even for those who might not be tech-savvy. It’s simply a case of clipping and inserting, and I actually found it easier to install than some of Kiwi Design’s other head straps.
The K4 Duo is a clear step up from the original design. While it keeps the familiar Kiwi Design aesthetic, it’s now 35% lighter and 30% slimmer, making it noticeably more comfortable, especially during extended VR sessions. Despite the reduced weight, it doesn’t sacrifice durability. It still feels solid and secure, giving you confidence that it’s built to last!
Weighing just 435g, the K4 Duo achieves an almost perfect front-to-back balance with the Meta Quest 3 or 3S. The addition of integrated headphones also helps centre the overall weight, making head movements feel smoother and more natural, even during fast-paced gameplay or quick turns.
One of the biggest improvements is the introduction of Kiwi Design’s DualFast Charging System. Meta Quest headsets are known for their limited battery life, but this feature tackles that issue directly. The K4 Duo includes a 45W smartphone-style battery that powers both the headset and the K4 Boost. When charging both devices at once, it splits the power to 22.5W, allowing you to fully charge in just one hour and enjoy up to 120 minutes of additional playtime.
What makes this even more convenient is that both the headset and the K4 Duo can be charged simultaneously using a single USB cable. With a maximum input of 45W, a full charge is achieved in around 2.5 hours, keeping downtime to a minimum and getting you back into the action faster.
One of the coolest things about the K4 Duo is its All-In-One Audio Solution, and it’s a total game changer! For the first time ever, Kiwi Design has combined both integrated audio and a battery into a single, streamlined strap for the Quest 3 and 3S. That means you can listen to your game and charge your headset at the same time, all through one USB-C connection. No extra cables, no mess. This is especially significant for Quest 3S users, as the device does not have an audio jack. It keeps your setup clean, your gameplay uninterrupted, and your experience more immersive than ever!
Tuned with gamers in mind, the K4 Duo takes audio to the next level! Kiwi Design teamed up with acoustic experts with over a decade of experience at LG and GoerTek to craft a custom-tuned EQ that truly brings your VR world to life. Paired with a unique PU+PEN composite diaphragm, the built-in speakers deliver crisp, powerful sound that’s been specially optimised for VR gaming. Every footstep, every soundtrack, every moment feels more alive and immersive than ever before!
Specifications
Dimensions: 250mm (L) x 280mm (W) x 135mm (H)
Weight: 435g
Form Factor: Audio Head Strap with Battery
Material: Plastic, PU Leather and Memory Foam (Cushion)
Battery Compacity: 7.7V/2650mAh/20.4Wh
Charging Compatibility:
Input: 5V⎓3A/9V⎓3A/12V⎓3A/15V⎓3A
Output-Battery: 9V⎓3A Output-Passthrough: 9V⎓3A
Driver: 40mm
Magnet: Neodymium
Frequency Response: 20 Hz –20 KHz
Impedance: 33 Ohms +/- 15% @1KHz
Sensitivity: 113~114.9dB SPL @ 1mW
Rated Power: 20mW(0.8V)
Once again, Kiwi Design has completely exceeded my expectations. The K4 Duo has genuinely transformed my gaming sessions on the Meta Quest 3, allowing me to fully immerse myself in my games without worrying about comfort or battery life. Whether I’m diving into intense gameplay, relaxing with music, or even watching a film, the experience feels smoother and more enjoyable than ever.
As I’ve said before, no one has come close to challenging Kiwi Design’s place at the top, and with this latest release, their reign as the true Kings and Queens of VR continues strong.
You can get yours here: K4 Boost Battery Strap for Quest 3/3S
Highly recommended
IndieCritical hasn’t received any compensation for this review as stated in Our Mission guidelines.
Positives
💚 Excellent spatial audio for games, music, and films.
💚 All-in-one design (audio + battery, no extra cables).
💚 Lightweight, comfortable, and well-balanced.
💚 DualFast Charging adds up to 2 hours of playtime.
Negatives
❌ The price is £129.99
