These are pictures of the limited slip collar I made for Yukon. The two rings come together when the outside clip ring is pulled. Yukon is a very thick-furred husky, and his actual neck is much much smaller than the circumference of his fur. The old thick red mesh collar he had stayed at a constant circumference and used to ride up to his ears when he laid down, and rubbed the fur up by the base of his ears nearly all off. This new collar relaxes and sits down by his shoulders, but when on lead, prevents him from slipping the collar off without the danger of choking.
I made one for him and one for Demon, as they seemed to try to slip their collars more often. These are not made for tie outs! Both my dogs run in the fenced yard. By their construction, you can see they are quite easily made with the right tools and materials.