Elastic and nylon straps that connect from the girth / lunge roller and clip onto the bit / lunge caveson.
They can be used for flat work and lunging.
Side reins help accustom the horse to the bit, and reward the horse when it gives or flexes to bit pressure.
They encourage balance and correct head carriage, help a horse develop self-carriage, and help stop a horse from over-bending in the neck.
Dee rings make adjusting easy and encourage even contact on both sides of the mouth