6mm Ring - Black Gold Plated - Over 925 Sterling Silver Ring - Wedding Band For Men or Women - For Wedding Engagement Anniversary Promise - Matte - Customized or Personalized or Engraved Ring Available. $59.00, via Etsy.
Mens Wedding Band - Titanium polished and satin | Minimalist titanium wedding band. Something like this would be perfect for Rob. It's sleek and simple, titanium is the hardest metal you can buy and it's inexpensive.