Lau also said that the OnePlus 6 will retain the company's signature "horizon line and characteristic curve" aesthetic, and that the phone will offer a five-layered Nanotech coating. Lau mentioned that glass has numerous advantages over metal, stating that the material conveys a "transparent, bright, and pure" feeling. From the post:

Appearance-wise, we've always maintained our signature horizon line and precise curve to the back of the device. From the OnePlus One to the OnePlus 5T, the horizon line and characteristic curve are important elements of our design language.

In addition to retaining the horizon design, we've also tried to incorporate glass materials on OnePlus 6. Although OnePlus is not the first manufacturer to use glass, we are confident that we are providing users with our interpretation of a familiar material.

OnePlus 6's glass design is centered around creating a "sense of value" and "premium hand-feel." As I mentioned at the beginning, people relate deeply to the products they use. We gave a lot of thought to how users should feel when they use the OnePlus 6. The advantages of glass over metal are manifold: glass communicates a transparent, bright, and pure feeling. The way glass transforms under different lighting is a particularly important challenge—the OnePlus design team tested over 70 glass prototypes before selecting the best one.

At the same time, we always want to create devices that feel premium to the touch. We care about the user's experience from the moment they touch the device. We also want our devices to feel burdenless in the hand, even after an extended period of use. OnePlus users have exacting standards for great industrial design. These standards often push and challenge us to meet our users' expectations, to commit an extra layer of detail and polish in everything we do.

As an example, the OnePlus 6's glass back contains five printed layers of Nanotech Coating, a first in the smartphone industry. We applied 5 layers of Nanotech Coating instead of 3, even though the degree of separation between each layer is extremely subtle and tough to discern. However, the additional layers give the back of the device a stronger impression of depth that our most demanding users will surely appreciate. Closely examine the OnePlus 6 and you'll indeed see this subtle nuance embedded in each device.