These lockrings when locked on will not come off. These are brand new with a very unique design. They are hinged to allow you to open them wide and much easier to put on the bird`s leg. When you close them they lock shut and can not be opened with out using something with a point, such as a ball point in the hole and they will pop open and may be reused time after time. EZ Lockrings Size 10 MM 50 pack