Over 100 different prototypes.
We've tried about 100 different prototypes until we zeroed in on what's the best and most comfortable for most people.
Every millimetre counts. The nozzle, how long it is, the thing that goes into your ear. How wide the nozzle is, it's what angle the nozzle goes inside. There were iterations on the bud itself to ensure comfort. Medical-grade silicone in order to make sure that you have no irritations. Comes in contact with your skin and stays in your ear the entire night.
The second thing is, I think an important design choice we made is that in all other sleep earbuds, the charging contacts face in towards the ear. And so, when you sleep on your side, you will feel those charging contacts against your skin. Some people are even allergic to these metals, and so they'll develop an allergic reaction.
What we did was, we said, "Okay, there's only silicon that comes in contact with the ear". Charging contacts and the communication pins, they're all facing outward because we wanted to create the most comfortable earbud in the world.