More commonly known as a choke collar or choke chain, this collar is typically made of a metal chain (although nylon or leather versions are available) with a ring at each end. After slipping the chain through one ring, the other one is tied to the leash, while the noose made by the chain is slipped over the dog’s head
This collar works by tightening around the dog’s neck when he either reaches the end of the leash or is corrected by the handler.
Since there is nothing limiting the choking mechanism in any way, it is very possible to completely asphyxiate a dog wearing a slip collar, and is therefore not a collar I recommend. It’s not a matter of ethics, so much as safety. These collars are very dangerous, because if the dog panics, he could very well kill himself. While it is possible for dogs to get into serious trouble wearing almost anything (even a body harness), this collar has a much greater potential to do grievous harm. Anyone who claims that there is no way a dog would pull hard or long enough to bring himself one heave from a syncope is either lying or misinformed. Given the right stimulus, dogs can be very determined! Most breeds were bred to withstand a lot of discomfort, and a dog intent on following his nose may not even realize that he can’t breathe!
Some trainers claim that taking the wind out of an enraged dog can placate him enough to get the situation back under control, where many other collars would just exacerbate the situation. Admittedly, though, these situations are rare and generally easily prevented with a bit of foresight.
There are nylon and leather choke collars on the market, but just like with the partial-slip collars, a metal chain will slide more fluidly, allowing the collar to release as soon as the dog (or handler) ceases to apply pressure.
Certain collars, such as Cesar Millan’s Illusion Collar have been created with the intent of keeping the choke mechanism constantly high behind the ears, eliminating the need to keep readjusting it. This type of collar is comprised of two collars: a choke collar that sits right behind the ears and a flat collar that sits low on the dog’s neck, these two are connected by a couple of narrow nylon-covered plastic plates that keep the aforementioned choke chain high up on the dog’s neck.
Some owners with sporting dogs find it opportune to keep their dog’s tags on metal choke collars as they don’t get dirty or smelly like nylon or leather ones; although, this increases the potential for the collar getting caught on something, so be extra vigilant. There is a kind of choke chain known as a fur-saver, which purportedly doesn’t ruin the dog’s coat in the same way that other collars would. It is comprised of oblong links, rather than closely-linked round ones.
While slip collars may be a convenient choice for dogs who don’t pull, as a collar on which to attach tags or a leash, they aren’t ideal for training a dog to not pull, as the correction offered by the choking they cause is often not an effective deterrent, and can be potentially dangerous.
Good luck, and happy training!
Always ask prospective trainers what tools they use and condone, as always, don’t settle for anything but clear, concrete answers! Check out Google+ for reviews on potential trainers.