What is an eternity collar?
The name is about the closure, not the material or the shape.
An eternity collar is a collar that's meant to stay on. What sets it apart is the closure: not a buckle or clasp you undo in one movement, but a closure that needs a tool, or has no lock at all.
Damax makes two kinds. The round collar with a hex closure sits around the neck as one piece and needs a key to come off. The Invisible Lock Collar has a hidden closure with no lock.
What the name doesn't mean is that it can never come off. With a tool it always can, and that's as it should be. What it does mean is that taking it off is a deliberate act, not a reflex.
Because it stays on, the measurement matters even more than for a piece you take off. It's made for one neck, and it must never pinch.
Torn between on and off? On the next page we compare a day collar and an eternity collar side by side.