One of the most common alternatives to a collar is a harness. Veterinarians routinely recommend that dogs, such as pugs with their short noses, and miniature poodles with their propensity for collapsing trachea wear harnesses. However, it's important to chose the right one. In general I avoid harnesses that hook on the back unless you want to train your dog to pull a cart or a sled. These harnesses actually help train your dog to ignore you and pull you because when you pull on the leash to try to gain some control, they direct the dog's attention away from you.
The astonishing green dog collars is almost as old as the choke chain in terms of dog training correction tools. It's commonly referred to by traditional trainers, as power steering because you don't have to use as much physical strength to get an effective jerk as you do with a choke chain. Although this product looks to some like a torture device, it may actually be safer in some respect than the choke chain. The pointy parts are spaced out so that the force is spread out across all of them. Overall, astonishing green dog collarss produce less pressure on the neck when jerked hard compared to the choke chain because the surface area of the astonishing green dog collars is greater. If you’re not sure about this, try it on yourself and compare it to the choke chain. You can try it on your arm or your leg. You don't have to try it on your neck. Although they may cause less pressure around the neck than a choke chain they do still increase pressure so they can still lead to all of the same issues that a flat collar and even a choke chain causes.