A double-jointed loose ring bit is a great choice a horse who needs more leverage and control. Bit guards can be added to protect the sensitive skin at the lips. Rubber bits are extra beneficial for sensitive horses because the mouthpiece is more flexible, and the rubber increases chewing and salivation.
Ring size in size 95, 105, 115 = 45mm. Ring size in 125, 135 = 55mm.
Rinse with water and wipe clean after each use.