K4 Boost Battery Strap for Quest 3/3S
- for Quest 3/3S
- Extended Play: Keep the MR sessions going with 3 extra hours of battery life. Optimized for peak performance based on your gaming needs.
- Dual Fast Charging, Twice the Speed: Simultaneously charge the K4 Boost and your Quest 3S/3 with the DualBoost Power system. Fully recharge both in just 2.5 hours with a 45W adapter, delivering 25W power to your Quest 3S/3 while charging the internal battery.
- Comfort and Balance: Ergonomically designed rear headrest with thickened padding reduces facial pressure, while enhanced counterweight eases strain on your head and neck.
- Safe and Reliable: The premium-certified batteries and system come with multiple layers of protection, including essential UL, EN, and FCC certifications. Every material is rigorously tested in TUV labs for safety and durability.
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Easy Wear and Quick Adjustment: The 52° damping hinge allows easy on and off, while the quick adjustment knob ensures a perfect fit.
Fast, Free Shipping
Fast, Free Shipping
Enjoy free shipping on all orders over $20. Experience fast processing & reliable delivery, with your order arriving in just 3–7 business days across the U.S.
※For more details, please see our shipping policy.
30-Day Money-Back Guarantee
30-Day Money-Back Guarantee
Shop with confidence and enjoy our 30-day money-back guarantee. Simply return your undamaged products within 30 days for a full refund—no questions asked. Once your item reaches our KIWI warehouse, we’ll quickly process your refund.
※For more details, please see our refund policy.
Hassle-Free Warranty
Hassle-Free Warranty
Enjoy peace of mind with our 18 month warranty. If anything goes wrong, we’ll make it right—whether it’s a quick repair or a full replacement, you’re always covered.
※For full details, please refer to the warranty card or our warranty policy.
Lifetime Customer Support
Lifetime Customer Support
Count on us for the long run. Enjoy lifetime customer support from our expert team—ready to help whenever you need it.
※Reach out via email or live chat—we’re always here for you.
Pay with Ease
Trusted Delivery
Which Battery Head Strap is Right for You?
Zero face pressure and lightweight comfort—ideal for casual gaming and entertainment.
Stable, secure fit with extra support—built for intense, high-motion gaming.
Built on the stable, lightweight K4 Boost design—now with seamlessly integrated audio for total immersion.
449g
364g
459g
Yes
Yes
Yes
5300mAh / 20.4Wh
5300mAh / 20.4Wh
5300mAh / 20.4Wh
Up to 2.5 hrs
Up to 2.5 hrs
Up to 2.5 hrs
Up to 45W
Up to 45W
Up to 45W
HMD + Strap
HMD + Strap
HMD + Strap
Forehead
Face
Face
Yes
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—
—
—
On-ear headphones, high-quality spatial audio
Let’s Answer Your Questions
Is this head strap better than the original one on the Quest 3/3S?
The original strap is lightweight and great for casual use, but the K4 Boost takes comfort and performance to the next level. It adds up to 2-2.5 extra hours of battery life, fast-charges both the headset and strap, and offers better weight balance with zero facial pressure. If you play for long sessions, it’s a solid upgrade.
What’s the difference between this strap and the H4 Boost?
The K4 Boost is designed for high-intensity movement and active gameplay, while still delivering excellent battery life. In contrast, the H4 Boost prioritizes comfort and extended playtime — making it ideal for relaxed gaming, movies, or work.
Will the extra head strap feel heavy?
Not at all. It’s built with industry-leading weight control and a balanced design that actually feels more comfortable than the original strap — even during long sessions.
Is the battery safe?
Yes, absolutely. We use high-grade lithium batteries that pass strict safety tests from the start. Plus, the product comes with an 18–24 month warranty or replacement policy, depending on your region.
Where can I find the user guide and warranty manual for the K4 Duo head strap?
You can download both the User Manual and Warranty Guide from our official support page. Just scroll to the “Battery Strap for Quest 3/3S (KW-QS02B-SPF)” section to find the PDF files.
