"Pet ID Tuub" - Pet ID Tag
Pet ID TUUBs are made by Goli Designs in Portland, OR. They're waterproof, stylish, durable and best of all, contact info is can be changed by cutting a new piece of paper to slip in. I prefer to use a thin-point permanent Sharpie-like pen. Unrelated to pets, they are also great to use as ID on keychains, purses, bags, and other personal belongings you'd like to be united with if lost.
They are composed of anodized aluminum alloys and are corrosion and water resistant. The small TUUB measures 1-1/16" in length by 0.4" in diameter and comes with a split ring for attaching to a collar. Each TUUB constains a paper slip for ID description and contact information. Additional information can be added by writing on any paper strip of the same width, and insert into the TUUB.