ThinLine’s Flexible Filly Grazing Muzzle Receives Patent

The United States Patent and Trademark Office (USPTO) has issued U.S. Patent No. 11,485,628  to ThinLine Global Inc. on the state-of-the-art Flexible Filly Grazing Muzzle.

The patent confirms the grazing muzzle offers features unlike any other on the market. These characteristics encourage horses to behave naturally while giving owners the peace of mind that their horse is happy and healthy.

After nearly a decade of design work, we are excited to have fulfilled our goal of creating an effective muzzle both horses and owners actually like to use” -Elaine Lockhead Castelao, Founder & CEO.

Studies have shown that horses with metabolic issues, like Cushing’s disease, insulin resistance, or “easy keepers” can benefit from using a muzzle to decrease the amount of sugary grass consumed. By doing this, these horses are at a much lower risk of developing laminitis, equine metabolic syndrome, and other preventable problems.

Why this muzzle?

This muzzle is softer, safer, and smarter than traditional cage/bucket-like situations of the past. The Flexible Filly Grazing Muzzle comes in 2 grazing hole sizes that can easily be enlarged with scissors, allowing options to fit your horse’s exact needs.

For optimal grass intake management, ThinLine suggests using the restricted size during spring and utilizing the 3.5+cm hole size in the summer due to the increased grass thickness and length. However, talking with your veterinarian about your horse’s specific needs is recommended.


  • They are breathable, flexible, and offer UV protection that acts like sunscreen for those delicate noses.
  • Works well with automatic waterers and encourages proper equine hydration.
  • It will never rub, it’s lightweight, and allows horses to engage in natural behaviors.

ThinLine researched equine behavior to learn why other muzzles don’t do the trick so a simple solution for safer grazing could be created. Horses can still groom each other while wearing this muzzle, scratch themselves, and behave the way nature intended, like horses! Protect your horse this spring and talk to your veterinarian about grazing practices and management.

As always, contact your veterinarian about your horse’s specific needs before changing your horse’s routine.

Read the reviews from happy horse owners, learn how to select the proper size, and see more at 

To learn more about ThinLine products, visit

ThinLine Global creates products focused on comfort, safety, and performance for horses and their riders. We make the feel softer and more effective while protecting horses for peak performance. ThinLine provides solutions from saddle fit to rider confidence and security. Additionally, ThinLine manufactures other innovative accessories to keep your horse happy and healthy.

Images available upon request.

Media Contact:
Maggie Carty
Marketing Manager
ThinLine Global
3430 Coates Industrial Blvd #300
Durham, North Carolina, USA 27705