Flexible Scope Eye Enhancers are made from Thermoplastic polyurethane (TPU) 92A, making this a firm but still flexible eye enhancer great for not losing shape to encourage shooters to stay centrally behind the scope, a slight deviation from the centre can introduce parallax errors resulting in a missed target. Eye enhancers come standard in Black included with scope clamp, other Eye Enhancers colours maybe available in the near future.