The base of the hat is four tubes taped into a square, which are pulled snug onto the head. The tubes deform into an oval and grip the skull nicely. For the base I used tubes of 12" length, 1" width. Definitely buy some of this specific size for the base.

As the foundation of this hat, the base withstands the most abuse. The electronics will be mounted here, and it will be rubbing against your head all week, so some armor is in order.

I tried liquid plasti-dip for a rubber coating, but the dipping and drying process was a huge pain and I went through a $16 can quickly.

I also tried aerosol plasti-dip, but the resulting layer was uneven and super thin. And it smelled like poison.

For my (mostly undocumented) 2015 hat, I taped every tube on the hat for ultra-durability. None deflated.

For the 2016 build, I ran an experiment in my Snapchat story, asking which version looked cooler.

12-1 vote in favor of translucent tube.