A horse shaking its head when bit pressure is applied or its tongue trying to escape the bit are classic signs the horse has a sensitive tongue. With this in mind the McHardy was created, it has a medium port creating space for the tongue relieving pressure. The Buster Roller in the middle increases bar pressure and as a result lifting the horse's head and giving more control.
The mouth piece is made from blue sweet iron, because it:
helps bit acceptance
is warm and sweet
Please note the blue will fade with use.