The Hard To Kill Cat Eye is a highly detailed, Glow in the Dark, custom molded 3D logo with a hook backing. Tardigrades or "Water Bears" are nature's microscopic terminators, able to survive in the most inhospitable conditions.“Cat Eyes” have been in use the US military for decades. Anyone who has ever used a helmet band or patrol cap knows what these are. They can be used in pairs or individually. Our Cat Eyes are a high grade of non-toxic, durable PVC. The hook backing allows the Cat Eye to be fixed to any loop swatches found on headwear, packs, plate carriers, webgear and more.