This is the English edition of a review from my Japanese YouTube channel, iestaLife. I review gadgets from my home studio in Japan, so product links go to Amazon Japan. I bought this power bank myself.
Quick take
CIO's SMARTCOBY Ex04 looked like my ideal power bank on paper: a semi-solid-state battery, MagSafe-style magnetic wireless charging (Qi2.2 according to the listing), and a built-in, detachable USB-C cable for wired charging. In use it does everything it promises, which makes it a great single power bank for travel. The trade-off is bulk: it measured 14.1 mm thick, about 1.5 times the slim 5000 mAh packs I usually carry, and its magnet is a little gentler.

What I tested
- CIO SMARTCOBY Ex04 Wireless2.2 CABLE SS5K (a little over ¥7,000 at the time of recording)
- CIO SMARTCOBY SLIM 5K, magnetic wireless only (list price ¥5,980), the one I use day to day
- A MOMAX 5000 mAh pack that sticks on magnetically but charges by its built-in cable only (just under ¥5,000)
- An iPhone in a MagSafe case
Measurements
| Power bank (charges by) | Thickness | Weight | |
|---|---|---|---|
| CIO SMARTCOBY Ex04 magnetic wireless + built-in cable | 14.1 mm | 146.8 g | |
| CIO SMARTCOBY SLIM 5K magnetic wireless | 8.8 mm | 121.4 g | |
| MOMAX 5000 mAh built-in cable | 9.3 mm | 119.4 g |
What I found

- Wired and wireless in one. Wireless charging is convenient but runs warm, is slower than you hope, and loses energy along the way. With the same 5000 mAh, wired charging gets more of it into the phone. Ex04 lets you choose either.
- The cable is a highlight. It doubles as a strap loop and can be detached. You can recharge the pack through that cable or through the separate USB-C port, so you never need to remember a cable.
- Numeric battery display. Press the button on top and the remaining charge appears as a number. It also shows when it is charging the phone.
- The cable plug is straight, so wired charging with the pack on the back of the phone sticks out below. When I am not in a hurry, magnetic charging is the neater option.
- Thickness: 14.1 mm versus 8.8 to 9.3 mm for the other two. The 20-odd gram weight difference is not a big deal; the thickness is.
- Magnet: noticeably gentler than the SMARTCOBY SLIM. It will not drop off in normal use, but I expect it could get knocked off in a pocket or bag, so I would use the cable when it is in a bag.

Who it is for
- Travellers who want to carry just one power bank that handles every situation
- People who keep forgetting cables
- Anyone bothered by heat and losses from wireless charging
- If thin and light for daily pocket carry matters most, a slim magnetic-only pack such as the SMARTCOBY SLIM 5K is the better pick; if wired-only is fine, the MOMAX has an L-shaped plug that does not stick out
Watch the review
The video is in Japanese (YouTube can show auto-translated captions). Useful chapters: 02:01 unboxing and measurements, 04:27 the cable and charging tests, 06:06 pros, cons and verdict.
Limitations
This review covers first impressions right after unboxing, not long-term battery health or charging-speed measurements. Prices are Amazon Japan prices at the time of recording.
Products
CIO SMARTCOBY Ex04 Wireless2.2 CABLE SS5K: on Amazon Japan
CIO SMARTCOBY SLIM 5K: on Amazon Japan
MOMAX 5000 mAh power bank: on Amazon Japan
The Amazon Japan links above are affiliate links. As an Amazon Associate, I earn from qualifying purchases. Check the listing for the exact model, current price and shipping availability in your region.
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This review is also available in Japanese.



