Most 10000mAh power banks weigh about as much as a full can of soda and treat a rainstorm like a death sentence. The KLARUS K5 goes the other direction: a full carbon-fiber shell, real waterproofing, and a weight of 157 grams — roughly a third lighter than a typical power bank this size. It’s built for hikers and travelers who count grams, and on paper it’s one of the most interesting small chargers we’ve seen this year.
See the current listing here: KLARUS K5 at the KLARUS store
Full disclosure before anything else: KLARUS did not send us a review unit for this one, and we haven’t put our hands on a K5 yet. This first look is built from the manufacturer’s published specifications and the product details the brand shared with us directly. If a unit reaches us, a full hands-on review — with real charge-time tests — will follow and this page will be updated. What follows is what the specs actually say, including the parts most listings hope you won’t read closely.
Quick Answers
- What is it? A 10000mAh pocket power bank wrapped in a full carbon-fiber body, rated IPX8 waterproof, weighing 157g and just 13.6mm thin.
- Fast charging? Yes — up to 22.5W over USB-C with PD and QC support, plus a USB-A output for a second device.
- Where is it sold? Only through KLARUS’s own store — it is not listed on Amazon.
The Specs That Matter
- Capacity: 10000mAh / 38.5Wh high-density lithium cell. The honest number to know: rated output is 6,400mAh at 5V. Every power bank loses energy in conversion — the K5 publishes its rated figure, which is more candor than most brands offer. In practice, expect roughly two full charges for a typical phone.
- Output: Up to 22.5W fast charging (PD/QC). USB-C port handles both input and output; a USB-A port outputs to a second device.
- Body: Full carbon-fiber wrap, 105.7 × 63.4 × 13.6mm — genuinely pocket-thin — at 157g. KLARUS notes a typical 10000mAh bank runs about 230g, so the weight savings are real, not marketing rounding.
- Waterproofing: IPX8 rating per KLARUS’s own product page — the strongest common waterproof grade, built for sustained wet conditions, not just splash resistance.
- Display: An LED readout shows remaining battery as an actual percentage number, not four vague dots.
- Low-current mode: For earbuds, smartwatches, and other small devices that big power banks often refuse to charge properly.
- In the box: The K5 and a USB-C to USB-A cable.
Who This Is For
Ultralight hikers, backpackers, and anyone whose charger lives in a bag that might get rained on. The carbon-fiber shell also shrugs off the drops, vibration, and temperature swings that kill plastic power banks in a work truck or a trail pack. If grams and weather resistance don’t matter to you, cheaper plastic 10000mAh banks exist everywhere — you’d be paying for the two things this one does differently.
What We Can’t Tell You Yet
Specs don’t say how fast it charges a specific phone in the real world, whether the IPX8 seals stay trustworthy after a year of pack abuse, or how the finish holds up against keys and tools. Those answers need a unit in hand. When one arrives, we’ll test charge times, dunk it, carry it for a few weeks, and update this page with results — good or bad.
Bottom Line
The K5 is a specialist tool: the lightest serious waterproof power bank in its class on paper, from a brand that publishes its real rated capacity instead of hiding it. If your charger rides in a hiking pack or a truck console and has to survive weather, it’s worth a serious look.
Check the KLARUS K5 here: KLARUS K5 at the KLARUS store
BuySmart Daily works with KLARUS through Levanta. This article was written from manufacturer specifications; no review unit was provided, and no hands-on testing has been done yet.