The French link has proved one of the most popular bits. 2 joints means the pressure of the bit is distributed over both the tongue and bars of the mouth. The mouthpiece has two joints, it shouldnt cause any interference with the roof of the mouth. The French link uses tongue pressure to encourage the horse to go on the bit and has bar and lip pressure but not a squeezing action like that of a bit with a single joint. The more joints a bit has the less likely the horse is to lean as the bit becomes more mobile. Full Cheek bits are a fixed cheek bit, this may be useful for horses that are a bit unsure of the bit as it doesnt move around to much in the mouth, it should encourage the horse to stretch into the contact. Full cheek bits are very useful for breaking in, or bringing on of young horses, as they help tremendously with the turning aids, and the full cheek bit does not slide through the mouth as would a normal snaffle if your horse doesnt like to turn. The bit is particularly useful for horses that nap, as the bit will help if the horse suddenly turns. The full cheek bit works by applying pressure to the cheek when a turning aid is given. Ref: UTWB312