An animal collar is a device that attaches to the neck of an animal to allow it to be harnessed or restrained. Types of collars Pet collar A piece of material put around the neck of certain pet animals, such as dogs, cats, or pigs, for control, identification, or other purposes. Identification tags and medical information is often placed on collars. Collars are also useful for controlling the animal, as they provide a handle for grabbing or a means of leading. Similar collars are used with non-pet animals, such as zoo animals and livestock. Pet collars can be made of leather, nylon or metal. Metal collars are normally used for larger dogs. They can come with traditional or quick-release buckles. Collars are sometimes used for fashion purposes. Cat collar Similar to dog collars, but often include a bell to warn of the cat's presence. Collars used on cats are smaller and thinner than traditional dog collars. They can be made of leather, nylon, or other types of materials. Some cat collars are impregnated with flea, tick, and mosquito repellents. There is a longstanding myth that breakaway cat collars are safer than buckle or elastic cat collars, but research reported in the New York Times found this to be untrue. According to a different study, cats are much more likely to be injured by fighting with other cats or being hit by a car. Anti-bark dog collar/bark control collar These collars are predominantly used as a training mechanism. There are a few different types of mechanisms which can be incorporated into anti-bark collars: Citronella The citronella collar releases a spray of citronella-scented liquid when the wearer barks. Most dogs find this scent unpleasant and will resist further barking. Static shock This collar emits a shock through two metal prongs that touch animal's neck. The shock will increase in intensity if the barking continues. This kind of collar is illegal to sell in the UK but is popular in the USA. Sonic Dogs can hear much higher pitches than humans. This collar sends an unpleasant pitch when the dog barks. This collar is tested for each dog to ensure that the pitch is perfectly tuned. Vibration These collars often feature both sound and vibration. Instead of using sonic, they use a low pitched beep when barking begins. This is soon followed by a vibration if barking continues. The vibration is harmless. Training