Huawei P20 prototype images have leaked with no volume buttons. To be clear, there are actually volume buttons on the device, but according to the leak the physical volume keys which you will find on every other smartphone are non-existent. In their place are what appear to be touch-sensitive volume keys. To adjust the volume, users of the Huawei P20 would either slide their fingers up or down, or it could be possible that a segment of the touch-sensitive area will allow for tapping to turn the volume down while the other area would allow for the same interaction but for turning the volume up, not too unlike the method used for the Google Home Mini.
In addition to the lack of physical volume keys on the side of the device, the back of the phone features a dual camera setup which goes against some of the rumors suggesting that it would come with three camera sensors, making it the first device that would come with such a feature. That said, Huawei may be releasing a Plus or Pro model of the P20, and the leak states that this would likely be the three-camera model of the device.
The P20 looks relatively thin in terms of design, and Huawei seems to be using a bezel-less style display with an 18:9 aspect ratio which follows the trend of this design trait found on other phones which are already available. The prototype doesn't power on so it's not easy to tell exactly where the bezels on the side begin, but they do look as if they're not really there. Though Huawei will likely offer the P20 in multiple colors just as it did with the P10, the prototype shown in the images below is Black, so there will at least be a Black option for the phone when it launches later on this year. A couple of final noticeable traits about the prototype include the use of USB Type-C, which is nothing new as Huawei used this port on the P10, but next to the port, rather on either side of it for the P20 prototype, are what look like stereo speakers, so it's possible that Huawei could have bumped things up from just one speaker with this new device. That said it's also possible that only one of those sets of speaker holes could be a speaker while the other could just be there for uniformity of design.