Mecate reins are a type of rope used to lead and control a horse. They are typically made from either horsehair or nylon and are attached to the halter at the bit end, running through the eyelets on the crownpiece, and terminating in a loop at the noseband.
The ideal length of mecate reins varies depending on what purpose they will be used for and what type of horse they will be used on. For example, shorter reins (around 6 feet long) are often used on ponies or horses that are being ridden in an arena setting, while longer reins (up to 25 feet long) may be used when working with cattle or out on the trail. Ultimately, it is up to the rider to decide what length will best suit their needs.