There are so many different types of collars, it really is a personal preferance. the leather ones are nice, and good for show dogs to not ruin their coats.

Personall, we use the nylon slip collars, or Martingale collars. They tighen a certain amount on the dog, so that they can not back out of them and safer then a choke collar, that will continue to tighten. Premier, is the brand we use, and they also make the "Chinook", which is a break away collar, that will realse the dog if they pull becuase they are caugh on something.

Here's a link to check out the collars...

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