The Spinner on this Bombers bit is formed of two circular rings that sit on top of the tongue. They move with the tongue to prevent the horse from putting his tongue over the bit or rolling his tongue up behind the bit.
Together with the blue sweet iron mouthpiece, which oxidises in the horse's mouth to create a warm, sweet taste, this bit from Bombers Bits encourages mouthing, salivation and acceptance of the bit. It is designed to make the horse more relaxed in his mouth and encourages him to go forward into the bridle, rather than ducking behind the bit.
Full cheeks can be useful for horses that are unsure of the bit, because the bit doesn't move around so much in the mouth as it would do with loose rings, therefore encouraging the horse to stretch into the contact. The full cheeks also help to prevent pinching at the sides of the mouth.
The arms of the full cheeks assist with steering, as pressure is applied to the cheek when a turning aid is given. The cheeks also ensure that the mouthpiece remains in a central position and cannot slide through the horse's mouth.
Please note that the blue will fade with use.