Ring with 18mm inner diameter. Has a 180 degree twist, like a mobius strip. Shown printed in Polished Silver and Matte Black Steel.
Newer Version is available
here (more comfortable, lower cost, multiple ring size variants).
Says "LIVE THE LIFE YOU LOVE THE LIFE YOU LIVE...", paraphrasing "live the life you love, love the life you live";
18mm is ring size UK P or US 7 3/4.