Note: Please check the product section or the video in this product listing (XL-Black), which will teach you how to train your dog to accept the muzzle.Measurements: Measure the circumference of the dog's mouth and dog's neck. Please check the second picture and choose the right size. If you're torn between two sizes, the smaller will fit better. Please check carefully before purchasing.ADJUSTABLE: Different sizes to fit different breeds, so you can find the perfect size for your pup.HIGH QUALITY: Made of durable, high-quality nylon that can withstand everyday use and is comfortable to wear.PREVENT BITES: Great for aggressive and energetic puppies, use during training or on daily walks around. Note: 1. Please allow 1-3 mm error due to manual measurement and 1-3g weight error make sure you don't mind before ordering. 2. Due to the lighting of the photos and the difference of monitors, the pictures may not reflect the actual color of the real item. Please make sure you don't mind before ordering, thank you! About Shipping: 1.please pay attention to your delivery address such as: name, street, house number, doorbell/email without name, etc. is correct, or the order will not be delivered correctly. 2.All items will be shipped within 3 business days after the payment is received. Most times you will receive them within 8-12 days then. The specific delivery time is depend on circumstances. 3.During the shopping process, if you have any questions, please feel free to consult us, we will reply you within 287 hours Hope you have a pleasant shopping experience!