The adapter was designed to be tightened with significant force against the walls of your cup holder. Since this item is 3d printed, I was able to utilize mechanisms not possible with traditional methods, allowing the adapter to exert such a high holding force.

The expanding mechanism can be operated from the top of the adapter both with the top screwed on it and without. Simply turn the blue adjustment knob to the right to expand/tighten the adapter.

See installation video for a visual demonstration.

The top portion which holds bottles and mugs screws on to the expanding base, allowing it to be easily removed and interchanged with other tops for other bottles. Each top is specific to a certain bottle, meaning you can be sure it will work for you.

This is not a mass produced item. After experiencing how cheap and unstable mass produced universal adapters were, I designed and created this item to solve my own cup holder issues. After testing I realized just how much better it was than others, and decided to sell it on my website.