MagSafe battery backup/charger sought

Any recommendations for a battery backup/charger for a MagSafe MacBook Air? I looked at the recommended one from the MPU travel show, Mophie, but they only have usb-c types. Also what’s the deal with bringing these on airplanes? I saw some that said they were not allowed. Thanks.

The only one I’ve ever heard of is one from HyperJuice:

As they note on their page, Apple doesn’t licence MagSafe to anyone though.

As to battery limitations on planes, it depends on the airline and country - e.g. China is much stricter about the size of the batteries than Europe or the USA in my experience. These kinds of batteries should not be checked according to the regulations of most airlines.

Is there some alternative? I feel like I’m not understanding a basic concept of extending battery life while traveling and away from AC power. What did traveling folks do before USB-c?
A question to all.

Used paper and pencil, mostly.

I always liked the MacSafe, but this was definitely a disadvantage. Apple didn’t license it, so no third party batteries are available. The HyperShop people have gotten around that I think by buying Apple power adapters, taking them apart and reusing them, but that’s expensive.

Everyone complains about USB-C, but the ability to use external battery packs is an advantage I rarely see mentioned.

I travel 30+ times a year (including many trips to sub-Saharan Africa) and never felt the need for a battery for my MBP. What I always have with me: universal travel adapter.