The Type-C interface has now become ubiquitous across various mobile devices. A primary reason for its popularity is undoubtedly the convenience of its reversible design， a significant improvement over the previous micro USB interface.
Micro USB， a portable version of the USB 2.0 standard， was finalized in 2007 by the USB Implementers Forum (USB-IF). With the advent of Android smartphones and tablets， micro USB became the standard for these devices (excluding Apple). It also saw widespread use in other digital products like power banks， Bluetooth earphones， cameras， and dashcams.
Observing the micro USB connector， its asymmetrical design， being narrower at the top and wider at the bottom， with the data pins situated next to the longest edge， was a clear attempt at a “fail-safe” design. However， this required users to orient the connector correctly for charging or data transfer， a process many found inconvenient and even frustrating， potentially disrupting the user’s flow， especially during nighttime charging.
The symmetrical Type-C interface， which allows for reversible insertion， has therefore been widely welcomed. The underlying USB 2.0 or 3.0 standard seems to have become less of a primary concern for many users in comparison.
While Type-C is now the dominant standard， a considerable number of devices still utilize the older micro USB interface.
To improve the user experience， a reversible micro USB plug has been invented. This innovation requires no modifications to the device’s port itself; instead， a completely redesigned plug achieves the desired convenience of being pluggable in either orientation.
As the image above shows， the new micro USB plug eliminates the original asymmetrical design， presenting a horizontally symmetrical interface， much like Type-C. It even retains the familiar spring clip mechanism for securing the connection， giving it a resemblance to a game gemstone.
Furthermore， the plug’s pin area has been redesigned with two slots， effectively enabling reversible insertion. It’s quite remarkable how the micro USB standard has been ingeniously modified to achieve this functionality， something the USB-IF might not have initially envisioned.
While this reversible micro USB design offers significant convenience， it’s important to note that it still operates on the USB 2.0 data transfer standard and has very limited fast charging support. Given that Type-C has largely taken over the market， this micro USB modification could be seen as a “nice to have” rather than essential. However， for those with older devices that are still in use， such cables still hold considerable utility.
