The Medium Ring Gag is stronger than the usual Loose Ring and Eggbutt as the ropes going through the rings create leverage which will exert more pressure through the mouthpiece whilst at the same time introducing more poll pressure.
The Colin Miles is a great schooling bit with a 55 mm center piece creating greater tongue pressure and reducing bar pressure. The rings give the horse something to play with and help keep the horses attention on the bit.
This particular joint exerts more pressure than the Control Plate or Elliptical.