They are made with a chain or a nylon ribbon with two rings at the extremities. Insert the chain in one of the rings, slip the collar on your dog and attach a leash to the other ring.
If the dog pulls ahead the collar will tighten, making a special sound.
This will help you communicate with your dog about the speed and the direction you want to take without the need for you of using any force.
This video from Petmate explains how to choose the right size for a dog choke collar and how use this comfort chain collar.
There is a right and a wrong way to put on your dog a slip collar.
When the dog walks on your left, the ring with the leash attached comes on the left side of the dog's neck. If you look at the dog from the front, the collar should form a P (like Perfect) with the loop of the P around your dog's neck.
To test the effect of a training collar, it is a good idea to try it first on yourself. Before using this collar on your pet, put it around your arm and pull to test how it will feel on your dog.
You can also ask a friend to "take you for a walk" to practice how it feels being trained before you actually train your dog.
The dog choker collar or better said, the training or slip collar, can be useful to guide and gently direct your pet.
It is very important that you never leave a choke collar on your dog when he is unattended, the free ring can get caught and the chain can work as a noose with disastrous consequences.
Remember to use this kind of collars very gently and only during a well planned training session.
Collars with smooth links work better because the ring slides better on the chain and immediately releases the pressure as soon as the dog gives in.