I've been buying the "super reflective" dog ID tags for years and I must say they are the best I've ever found. All of the info about you and your dog is sealed so that water won't affect it. It is as permanent as a dog ID can be. The tags are highly reflective too, which means that if your dog happens to get loose at night he or she will be easier to see. If you want to maximize the chances that your lost dog will not be hit by a car and will be reunited with you, this is the ID tag to buy. This is one of those high-quality products that I go out of my way to buy. In fact, we just got another dog and I just ordered a "Super Reflective" tag for her. I can't recommend this product highly enough. And the service I've had when ordering it from Petmarket has always been first-rate.