Sweet iron will rust when it comes into contact with (air) humidity; the surface rust tastes sweet and naturally stimulates the saliva production. This will cause the horse to salivate more which in turn encourages better acceptance of the bit. The rusting process (oxidation) changes the blue colour of the TRUST-bit to a brownish-grey.
If a sweet iron bit is not used for a while, an orange-brown rust layer may develop on the mouthpiece. Simply remove this by wiping the bit with a damp cloth.
A Kimblehook is a bit that belongs to the category of the Pelhams, but only one rein is used. The effect of a Kimhook is softer than a pelham. The lower the rein is placed, the sharper this bit will be.
The effect is bigger when used in combination with a curb chain.
This bit finds its origin in the driving sport, but is also popular with show jumpers. The Kimblehook bit is not suitable for inexperienced riders and horses.