The EzyDog Checkmate Collar is a unique version of a martingale training collar. The Checkmate collar is a reliable and secure dog training collar, designed to be safe and secure, with all the benefits of a martingale. The limited-slip functionality humanely provides ultimate control and handling over dogs who need correction. The Checkmate does not require the act of resizing for each fitting. It is humane and safe with proper use. This comfortable collar features reflective stitching and is made from durable nylon.