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by _jackdk_ 18 days ago
USB-C maximalism is great for travel. I personally recommend travelling with a USB-C desktop charger, but use one that accepts a IEC C7 ("figure-8") cable. Then, travel with only the cable corresponding to your destination (or buy one when you get there). That avoids having a wall wart that might not fit in narrow spaces, or whose weight might make it fall out of older sockets.

I wrote about it a few years ago; the post does not have affiliate links: http://jackkelly.name/blog/archives/2024/10/06/travel_tip_us...

10 comments

If you’ve got one of the older style Mac chargers, the part which plugs into the wall physically separates from the rest of the charger. You can connect different plugs for all the different countries. There is a plastic seam where the charger separates. It’s easy to miss.

I’ve slowly acquired all the global adaptors for Mac chargers. I just bring a usbc Mac charger when I travel with the destination country plug attached.

I wish Apple made gan chargers though. Those look great

Those Apple chargers in fact use the C7/C8 connector to interface the plug adapter, so you can skip their official parts and use any compatible cord.

I for years used a power cable from an Xbox with my old Magsafe1-era Macbooks.

Huh I was going to say you may be talking about a differen thing, but I checked and they actually are C7/C8: https://ptcomputers.com.au/wp-content/uploads/without-power-...

So in this universe Apple doesn't invent its own standards...

You might or might not be very surprised to learn they recently abandoned the C7/C8 https://www.macrumors.com/2026/04/02/apple-140w-power-adapte...

Even the MacRumors commenters who are generally cheerleaders are scratching their heads about this one. And so do I.

Unless, as purplefox speculates:

> My guess is that's a fake one.

I've seen fake Apple chargers in local shops recently, with complete Apple packaging, "made by Apple in California" etc. and only detectable by close inspection of the details, specs not matching any Apple product, device info reported electronically that doesn't match any Apple specs, and the tiny inset writing not making sense when looked at under magnification. So that sounds plausible to me.

There is a detailed teardown here: https://www.chargerlab.com/teardown-of-apple-140w-usb-c-powe...

And a discussion here: https://discussions.apple.com/thread/256262949?sortBy=rank

And you will notice that the regular power adapter cable is not compatible with the new 140W charger: https://www.apple.com/au/shop/product/mw2n3x/a/power-adapter...

If you do that, you're losing grounding, which will result in the machine having that AC leakage buzz when you touch it. The chrome lug that the plug nub slides onto is a ground connection, and the Apple official cords and some country-specific nubs implement the ground brush connector. There is (was?) a third-party Schuko (not Europlug) nub.
Those power supplies often shipped with both a full cord input which was grounded but also a folding two-prong component that made it in to a wall wart and of course was not grounded.
The issue with a generic cord is that it won't connect the earth pin on those chargers.

But it does work in a pinch.

> The issue with a generic cord is that it won't connect the earth pin on those chargers.

Nor does the two-prong "wall wart mode" tip many of them shipped with. The ground was only connected on the extended cord attachment.

Same here, I used a black power cord from an old stereo.
At some point my older Mac charger that I was using for traveling died, so as a replacement I got a few of these styles of adapters: https://www.amazon.com/dp/B08YS7QHM9 (not the exact one I have - but you get the idea). I pair it with one of these: https://www.anker.com/products/a2687-anker-prime-charger-160... which is tiny for the amount of power it can output, which has been enough to cover both me and my wife while we travel. Many US plug chargers allow their pins to fold in, including this one, which makes for a fantastically compact setup when paired with that style of adapter.

Depending on where we are going and what we are doing, I also bring this thing: https://www.amazon.com/dp/B08YDPB8RZ which is kind of an extension cord + USB charger + all-in-one converter as well. The plug is at a right angle and very flat, so it can fit behind furniture and such that straight cables can't.

I do this too, the recent MacBook chargers have 2 usb-c and I have 4 of the plug parts that adapt it. Very minimalist but for short trips with single charger it is great

This might if you’re from the US as I’ve collected the ends over time, but I’ve never seen them for sale except the US one: AC Power Adapter Wall Folding Plug Duck Head,US Standard Plug Duck Head Compatible with MaBook Pro Air/Maci Book/Phone/Pod Power Adapter Brick

> I’ve never seen them for sale except the US one

Apple - at least used to - sell an international plug pack if you’re missing some. I can’t even remember where I got some of my plugs. They’ve been doing this for decades, and the international plugs are still compatible.

It’s been years since, but I bought on Amazon a bag of 8 different ends that work everywhere in the world.

It wasn’t from Apple, but it’s basically a plastic shape and 2 or 3 (depending on end) metal parts - it’s hard to get wrong, and easy to test before use.

New 70W Apple charger is GaN (and much smaller than the old 67W one) FWIW, it's a shame it is single port, though.
Older style? It’s still the case for the charger that came with my M4 MacBook Air.
I think your suggestion and also the author's are too big for my taste. I carry a US-style 45W GaN charger, a couple of usb-c cables, and an EU adapter (which, off the record, also works for UK outlets so it covers anywhere I normally travel to). I carry this daily and for travel even though I live in Europe as this combination is the same size as the EU version of my charger by itself.

For devices I have a work laptop, work phone, personal laptop, personal phone, headphones, usually a couple other small devices, and a mobile battery. I usually only heavily use my work laptop and personal phone. For phones and smaller stuff, I can charge them from the laptop while the laptop charges overnight so I don't typically wish for a second charger. If your laptop has decent battery life, charging at less than max speed is no big deal (I have two 16 inch MacBook Pros).

Additionally, I've converted most of my old favourite micro-usb devices like mouses to usb-c. A search for "usb-c 4.7kohm 5v female" will give you some options for replacing micro-usb with usb-c, with hobbyist soldering skills.

For a beard trimmer, I got an Enchen boost usb-c model for $10 for travel. It works well and even has ceramic blades but I had to add 4.7k resistors to work with a c-c cable[1].

[1] Cheap devices often omit some 4.7k resistors that tell a usb-c charger to output 5V, so it outputs nothing. This is why some devices work only with usb a to c cables, as usb-a outputs 5V by default. If you can manage to add the resistors to the correct pins or replace the connector with one that has them built-in, you can fix this problem. The difficulty of doing this varies a lot by device.

> and an EU adapter (which, off the record, also works for UK outlets so it covers anywhere I normally travel to).

What type of adapter is this? EU and UK plugs are very different.

I think they're describing how you can force the two pins of a europlug into a type-G socket, if you first stick a screwdriver or key or something into the earth pin to open the shutters.

This will give you access to electricity, but the contact area is much smaller than it's designed for (round pins in a rectangular hole), so using it for anything high wattage will end poorly.

An often overlooked part of the BSA spec for type-G sockets is they're supposed to have a flat surface surrounding the socket large enough to prevent you using the earth pin of an upside down plug to do this.

(Not recommended at home kids) use a key (or, safer, an upside down UK Earth pin) in the Earth hole to open the Live/Neutral shutter - then insert the EU prongs. The width of the EU prongs is handily the same as the UK holes.

Touring musicians do it if venues don’t have convertors.

Doesn’t work if the EU plug needs a live earth of course.

> It’s important that the charger accepts an IEC C7 cable. This is an international standard, so you’ll be able to find local mains cables at office supply stores or borrow them from nearby appliances, and it’s a two-pin design. Having a two-pin mains lead means you don’t have to worry about finding three-pin (earthed) power outlets in areas where they are not yet universal. It also means that an ultra-compact travel adapter like the Road Warrior can serve as a backup option if you don’t have a local cable.

An earthed-to-unearthed adapter (preferably with some alternate path to ground) seems like a better solution there than restricting oneself to C7 and its 2.5A max current. And when the ground prong is available in the outlet, it's often a useful mitigation against the looseness of worn-out sockets (since it adds another area of support).

> C7 and its 2.5A max current

If 250 W (in the absolute worst case, a 100 V .jp grid) is not enough for travel purposes, I have no idea what will satisfy your requirements.

I might need to power a lot of things simultaneously. I currently travel with a 6-port USB-C power adapter; while it doesn't blast max wattage over every single port (nor do I need it to quite yet), I'd be unsurprised if one that does eventually hits the market, at which point I'd be inclined to upgrade.

In any case, even for single-device power supplies, pretty much all of the 165W+ ones I have are grounded (either C5 or C13). This includes the one that came with my Framework 16 (which is my backup charger if I need to pack extra light or otherwise don't want/need that 6-port squid).

> USB-C maximalism is great for travel

It's honestly bliss when you get even close to it at home. I'm close, having only one Lightning device left (Apple TV remote) and a couple of USB-A and micro-USB devices I'll probably be stuck with for a while (avalanche pack, cat tracker, et cetera).

Yes! I've been doing this for years!

Figure-8 cable is usually easy to find in some old media player in someone's house.

That said usb-c chargers are quite ubiquitous now that you'll likely to find one anyway.

Also 6ft usb-c cables are very neat. IDK why Apple even ships that 3ft e-waste.

short, dumb one or two plug extension cords are great for travel. They're light on the wall side, so the travel adapter on that side generally stays in. Plus it's nice if you need a little extra reach occasionally
That sounds less janky than my solution: US wall wart charger -> 6ft extension cord -> international adapter.

(If you want to overvolt an extension cord, make sure it's completely passive: no light, switch, or surge protector.)

C7 is great advice.

But also pack a short length of cat5 twisted pair just in case. When all else fails, it allows to rig up most anything.

You should write up and publish your notes on how to fabricate connectors from cat5 wire, in the field. It would be a hit.
Cut by multiple bend, strip by teeth, curl enough to catch, insert, pull, twist.

Do you feel you need a write-up on how to piss in the woods too?

PoE maximalism would be interesting.
ABSOLUTELY DO NOT DO THIS BECAUSE IT IS INSANELY DANGEROUS buuuut...

... if you're hopelessly stuck without your cloverleaf charging cable you can kind of batter a figure-8 power lead over the phase and neutral pins, and you can probably find a figure-8 power lead more easily than a cloverleaf one.

Don't leave it unattended or where non-hackers can get at it.

Don't make a habit of it.

This will get you out of a hole.

My favorite DON'T DO THIS method is plugging European plug in UK socket - using something like scissors in earth to open shutters for neutral/live where EU plug actually fits pretty ok.

The other one is twisting US/JP plug pins so they fit AU/NZ sockets...

If it's one of those lovely old MK sockets like you used to get in the 70s/80s, then the earth pin doesn't open the shutter - it's opened by equal pressure on the phase and neutral pins. It takes a bit of jiggling to get the Euro plug to go in.

I keep both Schuko and UK kettle leads, cloverleaf leads, and figure-8 leads in my laptop bag, having been stuck before.

The best part is that you need to do this when you're on holiday, so all you've got are your keys, so you stab the keys into the slots and ever so carefully balance the round European plug contacts onto each key, and you pray to god that there's no earthquake and you don't cause a fire.

Or so I heard someone else do.

I have spent some time on this too.

I really wanted your approach to work and went down that pathway with this [1], but its one weakness if you have multiple destinations with multiple socket types. It's not uncommon that I have to go between countries with China/Aus, EU, India (kinda-sorta EU but not), and UK plugs. That's a lot of those C7 cables. Also, having 1-2m of cable lets you put the charger on a bedside table when the only wall socket is buried under the bed for some reason, so that adds up.

I then considered one with the swappable ends, like this [2], but the advantage of the cable is that you don't get the 'this room's only socket is against the desk and fuck you if you want to plug a big wall wart into it' problem, plus as above the cable lets the charger ports be much more easily accessible. Also, many models also only have US/EU/UK adapters, without covering e.g. CN/AU style plugs.

And at that point, you're basically using of those old-style universal adapters with the universal AC input and the sliders to change the output, especially given you can now get them with integrated 65W GaN USB ports [3], so why would you fiddle with attachments you could lose?

So then there's this [4] which is so close to my ideal but isn't quite there. It has the cable advantages, minimises additional swappable weight to get different socket types, and you can even put the adapters straight on the charger if you want to omit the cable. But then I read about abysmal reliability performance and I'd rather not burn down my hotel room in a third-world country. It does have the ends that I, personally, would like but with all of these you're at the mercy of them designing them for the specific wall socket types you need. And at least with this one, the UK one doesn't include a fuse as it's supposed to, whereas IEC C7 plugs do. Further burnination possibilities.

Really, if a reputable manufacturer made [4] but sank an extra ~50% product price into proper reliability and standards compliance, as well as making a whole plethora of swappable ends for all types of wall sockets that fit both the cable and directly onto the device, I'd probably buy it and never look again. I'd even accept a proprietary swappable end form factor with the vendor lock-in risks just because it's basically the utopian ideal of what I want.

But in the meantime, I'm back to using [1] with generic basic adapters for EU and CN/AU on the end of the UK IEC C7 cable. I'll build a collection of C7 cables for each destination and when I travel to only one I'll take the appropriate cable, but when it's multiple destinations I haven't found a better solution.

[1]: Ugreen Nexode 100W GaN 4-port charger: https://www.amazon.co.uk/gp/product/B0B6MZYKTF?psc=1

[2]: Ugreen travel charger: https://www.amazon.co.uk/UGREEN-65W-Fast-Charger-Ports/dp/B0...

[3]: Any permutation of this: https://www.amazon.co.uk/MOMAX-Universal-Adapter-Internation...

[4]: SlimQ 100W Charger w/ extension cable and swappable ends: https://slimq.life/products/100w-3c1a-usb-c-charger