Aristocrazy Anti-Escape Martingale Collar for Greyhounds and Escape Artist Dogs The Martingale Collar is ideal for escape artist dogs or those prone to pulling. Its adjustable design gently tightens when the dog pulls on the leash, preventing it from slipping off without causing discomfort. Safety, control, and style in one accessory. Materials The Aristocrazy fabric is composed of 65% polyester, 32% rayon, and 3% spandex, a combination that offers strength, elasticity, and a soft touch. Its elegant finish and firm structure provide a sophisticated style and great durability. With stainless steel hardware and buckles and reinforced stitching to withstand tension without deforming.