Why are there so many different reins in equitation? They are a vital part of equipment as they support communication with the horse, whether dressage, show jumping or horse riding in general, there is a growing need for reins of different materials.
Leather reins are very soft and supple with a great classic, upmarket look. They can, however, slip through your hands quickly when they get wet or if the horse starts pulling. This is why you see leather reins often with dressage riders. In dressage, the rider needs to be able to adjust the length of the rein very easily without disturbing the connection to the horse. In higher dressage classes with curb bits, mostly slimline reins will be used as the rider needs to handle 2 reins in each hand.
In showjumping, hunting and eventing, a lot more grip is needed than in dressage. To secure a firm hold on the reins even when the horse pulls, rubber reins and reins with stoppers are a great help. Also, they should have bigger stoppers for the martingale to avoid the rings of the martingale getting stuck with the hooks of the reins.
Most reins are available in different width. This is down to the rider's preference If 2 sets of reins are used, most riders will choose a slim set of reins. The same applies to children or petite females. Especially in training, there is no precise rule which reins need to be used. If you like to use more specialized reins like converter reins, it is always advisable to check with your federation first.