Dee Size: 2½"
Mouth Thickness: 14 mm
Mouth Size: 5"
I absolutely hate this bit. The rollers pinched my horse's tongue, making it bleed. The shape was awful and they should be illegal at shows, if not already. They were pure torture to my horse.
"Works for some horses, not all."
I bought this bit to use on my mares Sandy and Clairabelle, and they both detested it nomatter how I rode them. The rollers require the mouthpiece to be completely straight and round with no curve or taper, and they didn't like the shape of it. I gave it to my boss for use on one of her lesson horses who grinds his teeth, and he has never been happier in his life. The copper has held up well, and the rollers have made a tremendous difference in Splash's relaxation and flexibility.
I was very happy with how well this bit worked for my mare. The copper rollers make a significant difference in her salivation but I have not seen any damage to the copper yet. That was my largest concern, but after 4 months, it's still like new.