Dog shock collars are used for different purposes.  Dog shock collars may come in different styles; some may cause a shock, others may vibrate and yet others may release a very noxious smell.  Dog shock collars are designed to train the dog to stop unwanted behavior.  Small dog shock collars come in sets that include the collar with an attached receiver and a transmitter that sends the signals to the receiver.  The dog shock collars here have received the best customer reviews on their company sites and on different online sites.  The dog shock collars have been around for about 30 years now.