The snaffle bit creates direct pressure without leverage on the mouth.
The mouthpiece of the bit acts on the tongue and bars of the mouth (severity depends on the style) and the sides of the jawbone.
The loose rings allow the bit to move around within the horse’s mouth, which encourages further softening and mouthing.
When the rein aids are relaxed it allows the Loose Ring to distribute immediate release and relief from tongue and bar pressure, as the bit is immediately reset to a neutral position in the horse’s mouth thus rewarding a correct response.
The French link bit is more acceptable to horses with a low palate as it does not have the nutcracker action of the single jointed snaffle. The mouthpiece lays flat on the tongue and allows for more movement resulting in a lighter, offhand ride. The rein pressure is more evenly over the bars for a more independent control over the two sides of the mouth.