Herm Sprenger KK Universal Training Bit
This is the KK Universal snaffle bit. It is an excellent training tool for the dressage trainer, as the 3-rings enable the rider to have 4 different ways of attaching the reins to the bit. This allows different leverages and control. It is just as popular with trainers of other disciplines for the same reason. It is not legal in the dressage show ring, but really can help get the horse through training "hills" at home.
Sizes are transposed:
5" = 125mm
5.5" = 135mm (between 5.25 and 5.5"; closer to 5.5")
5.75" = 145mm