The most common mouthpiece amongst dressage riders is the double-jointed bit. A double-jointed bit consists of three parts. The middle part of the mouth piece rests on the tongue, which means the double-jointed bit exerts more pressure on the tongue than a single-jointed mouthpiece. The pressure distribution on the layers and the corners of the mouth is equal. Note that it is important to choose a double-jointed bit in the right size. If the bit is too large, there is a chance of small wounds as the joints touch the corners of the mouth. Do you want to know how to measure the right bit size? Read our previous blog here. When using a single-jointed bit, the tongue is freer than in the case of a double-jointed bit, therefore the bit works differently and exerts more pressure on the layers and side of the tongue.