Choke Collar: Choke collars are meant to provide a temporary correction. Tightening the chain around the neck gets your dog's attention. Releasing it implies that your dog is doing what you intended. When used correctly, it is not supposed to cut off her breath. The choke collar fits around the strongest part of your dog's neck. This in of itself can present an issue. The problem with a choke collar is that your dog can literally choke herself to death. Never leave a choke collar on your dog while unattended.
Electronic Collar: Also known as the shock collar, an e-collar needs to be used correctly, or it can cause more harm than good. An electronic collar, when handled properly, provides an immediate correction. Since dogs live in the moment, it is imperative that the shock is administered directly - in the split second - the time the undesired behavior occurs. The duration of the pulse should only be one-fortieth of a second and will feel like a mild electric shock.
Important: Always read your e-collar instructions for proper use! Otherwise, your dog may not understand why she is being shocked. And it may damage the trust between you and your dog.
Halter: Also called the halti, or head collar. A halter is designed to lead an animal by its head. This is the same way humans have managed larger animals much stronger than us, such as horses. A halter is also called a Gentle Leader collar. The halter works best on long-nosed dogs, such as German Shepherds. But, without proper use and fitting, it can be ineffective and uncomfortable. The downside to a halter is that your dog may not like the unusual sensation of a loop around her mouth. It is extremely important to have a halter properly fit so that it does not chafe your dog's nose. With proper fit and effective use, it can become a great training tool.
Harness: Harnesses were designed for pulling or tracking. Not for controlling. Huskies were harnessed to pull sleds over the snow. German Shepherds sported a harness to carry loads. And Saint Bernards wore harnesses to rescue people lost in the snow. A harness allows your dog to leverage its entire weight to perform a task. Remember this the next time your dog pulls you down the street while wearing a harness. While tracking, the harness allows your dog to have full contact with the ground, unlike a traditional dog training collar.
No-Pull Harness: Dogs that do not pull may be fine with a harness, but it may trigger a pulling reflex in other dogs. There are harnesses that are designed to be no-pull or anti-pull. These harnesses place a gentle pressure on your dog's chest when she pulls. The sensation is designed to be uncomfortable to discourage pulling. While they do offer more control than a typical harness, it is not the best idea for a dog that you already have difficulty in handling.