If you’ve ordered a new iPhone recently, you’ll notice that the box is a whole lot slimmer than in previous years. That’s because the bulkiest accessory is gone: the power charger.

A device that transfers power to smartphones, tablets and myriad portable devices. USB chargers plug into an AC outlet and provide a USB Type A or Type C socket to cable DC power to the device.

Unlike the iPhone, Apple ships a USB-C power adapter with all its MacBooks: Air and Pro. Unless your laptop stays in the same place all of the time, having a spare or a specific travel MacBook ...