Twist ‘n Treat is a patented toy that unscrews for easy loading of treats and fast clean up. The adjustable opening allows for a variety of treats from peanut butter to cheese bits to kibble. Best of all, the opening can be adjusted wider for easier access to treats or close it down for longer playtime. Dishwasher safe. Sizes: Small, Medium, Large Small recommended for Yorkies, Poms, Shih Tzus, etc. Medium recommended for Cockers, Beagles, Shelties, etc. Large recommended for Labs, Goldens, Rotties, etc. Comes in assorted colors, please allow us to choose for you. Thank you. Twist N’ Treat works well when filled with Simply Wild Pet Food.