Tom Thumbs or similar bits with long shanks can be really harsh on the mouth. Bits with shanks and mouth pieces like that are for very experienced horses and riders with extremely soft hands. They can cause alot of damage in the wrong hands.
Jazz, you said you had a green 4 year old gelding right? If this bit was meant for that horse, please do NOT use it. The best thing for a green horse is a snaffle. If you want your horse more responsive, train him to respond to light aids.