A halter, headcollar, or, less often, headstall, is headgear that is used to lead or tie up an animal; it fits behind the ears (behind the poll), and around the muzzle. To handle the animal, a leadline of strap or rope is attached to the halter beneath the muzzle.
Halters may be as old as the early domestication of animals, and their history is not as well studied as that of the bridle or hackamore. The word "halter" derives from the Germanic words meaning "that by which anything is held."
Halters are often plain in design, used as working equipment on a daily basis. However, specially designed halters, sometimes highly decorated, are used for in-hand or "halter" classes at horse shows and in other livestock shows. When an animal is shown in an exhibition, the show halter is fitted more closely than a working halter and may have a lead shank that tightens on the head so that commands from the handler may be more discreetly transmitted by means of the leadline. A shank that tightens on the animal's head when pulled is not used for tying the animal.
Halters are designed to catch, hold, lead and tie animals, and nothing else. However, some people ride horses using a halter instead of a bridle. In most cases, it is not safe to ride in an ordinary stable halter because it fits loosely and provides no leverage to the rider should a horse panic or bolt. It is particularly unsafe if the lead rope is used as a single rein, attached to the leading ring under the jaw.
Halters may be classified into two broad categories, depending on whether the material used is flat or round. Materials include cured leather, rawhide, rope, and many different fibers, including nylon, polyester, cotton, and jute. Leather and rawhide may be flat or rolled. Fibers may be woven into flat webbing or twisted into round rope. Flat or round dictates the construction method: flat materials normally are sewn to buckles or rings at attachment points; round materials are knotted or spliced. Knotted halters often are made from a single piece of rope.
In addition to the halter, a lead line, lead shank or lead rope is required to actually lead or tie the animal. It is most often attached to the halter at a point under the jaw, or less often, at the cheek. One exception to the practice of attaching the lead line under the jaw is the Spanish serreta, on which the lead line attaches at the top of the nose in a manner akin to that of the longeing cavesson.A standard working leadrope is approximately 9 to 12 feet long, though there are many variations that may be over or under that length.
A lighter version of a headcollar or headstall is also used to attach a fly veil of waxed cotton strands or light leather strips onto a browband.
Some Fly masks are also made in a similar pattern to a headcollar and are often fastened with velcro tabs. These masks may also have ear and nose protection added to them.
Horse halters are sometimes confused with a bridle. The primary difference between a halter and a bridle is that a halter is used by a handler on the ground to lead or tie up an animal, but a bridle is generally used by a person who is riding or driving an animal that has been trained in this use. A halter is safer than a bridle for tying, and in fact, a horse should never be tied with a bridle. On the other hand, a bridle offers more control when riding.
One common halter design is made of either flat nylon webbing or flat leather, has a noseband that passes around the muzzle with one ring under the jaw, usually used to attach a lead rope, and two rings on either side of the head. The noseband is usually adjusted to lie about halfway between the end of the cheekbones and the corners of the mouth, crossing over the strong, bony part of the face. The noseband connects to a cheekpiece on either side that go up next to the cheekbone to meet with a ring on either side that usually is placed just above the level of the eye. These rings meet the throatlatch and the crownpiece. The crownpiece is a long strap on the right-hand side of the halter that goes up behind the ears, over the poll and is buckled to a shorter strap coming up from the left. The throatlatch goes under the throat, and sometimes has a snap or clip that allows the halter to be removed in a manner similar to the bridle. Many halters have another short strap connecting the noseband and the throatlatch.
The halter design made of rope also has the same basic sections, but usually is joined by knots instead of sewn into rings. Most designs have no metal parts, other than, in some cases, a metal ring under the jaw where the lead rope snaps, or, occasionally, a recessed hook attachment where the crownpiece can be connected. However, in many cases, a loop is formed in the left side of the crownpiece and the right side of the crownpiece simply is brought over the horse's head, through the loop and tied with a sheet bend.
Lead lines are of varying names and types. The lead "shank" is flat, often made of nylon webbing or leather. Sometimes a flat lead line will be of the same material as the halter, though a halter and lead line may not necessarily match. Lead "ropes," as the name implies, are rope that can be made from a variety of materials, ranging from cotton or other natural fibers to assorted synthetics, such as nylon. Whichever type of lead line is chosen, they most often attach directly to the halter with a sturdy snap. Occasionally lead lines are spliced directly and permanently to the halter. When leading, some designs modify the lead shank to add a chain or slim piece of rope that tightens, most often over the nose or under the jaw, when the lead is pulled in order to provide extra control. This is particularly common with male breeding animals such as stallions.
Flat lead shanks and thin diameter ropes generally lack the strength to be used to tie a large animal such as a horse or cow, but may be more comfortable in a person's hand for leading. Ropes of a thick diameter (3/4 in or more) and high tensile strength generally are adequate to tie a large animal that resists being tied; thinner and/or weaker ropes will generally break if significant pressure is put on them.
There is a dispute over whether a halter should be made strong enough not to break under stress, or if it should give way when tension reaches a certain point in order to prevent injury to the animal. Usually the issue is of minimal concern if a tied animal is attended and the lead rope is tied with a slip knot with a quick-release loop that can be quickly released if the animal panics. However, in cases where a soft rope is drawn tight and the knot cannot be released, or if the animal is left unsupervised, an animal panicking and attempting to escape can be seriously injured. Those who argue that the risk of injury is more of a concern than the risk of escape recommend halter designs that incorporate breakaway elements, such as a leather crownpiece, breakaway buckles, or easily detachable lead rope. Those who argue that escape is the greater danger, or who have concerns that an animal that learns to break loose will be unable to be kept tied at all recommend sturdy designs that will not release unless the handler deliberately releases a slipknot or cuts the rope. Between the two camps are those who recommend sturdy designs, but with not-sticking styles of slip knots and materials that will not break under normal pulling back by a recalcitrant animal, but ultimately will break in a true panic situation, such as a fall.