Tumbler Cradle

Edit: Turns out these work great as bottle holders for the fridge.  Who knew?

Simple model that can accomodate a wide range of tumbler sizes.

Tested by my partner, who advises the friction is just right for applying wraps and waterslides as it holds in place when pressed, but slides easily when rotated.  However if a grippier surface is required, printing in TPU or applying stick-on foam/rubber strips would work.