The EzyDog Check Mate Collar is designed to prevent your dog's head from slipping out of the collar during walks or when they become excited. This dog training collar features a unique design where the collar tightens as pressure is applied via the lead, offering enhanced control. It does not require resizing for each fitting, ensuring a humane and safe experience with proper use. The collar is comfortable, includes reflective stitching for visibility, and is constructed from durable nylon with a welded stainless steel D-ring for leash attachment. A quick-release buckle closure allows for easy on and off. The collar provides ultimate control and handling. Available Sizes: Small - 26 - 34cm neck / 1.2cm collar width Medium - 34 -45cm neck / 1.9cm collar width Large - 44 - 65cm neck / 2.5cm collar width XLarge - 56 - 83cm neck / 2.5cm collar width