WIDE, FLAT SIDES AND RUGGED TREAD DESIGN * SUPER COMFORTABLE * GREAT STRETCH * A UNIQUE FEELING SENSATION AVAILABLE IN GLOW BLUE & GLOW GREEN DIMENSIONS: INNER DIAMETER: 0.8125"HEIGHT: 2"WIDTH: 2"DEPTH: 0.625"THE LATEST GLOW-IN-THE-DARK TECHNOLOGY IMMERSE UNDER BRIGHT LIGHT OR IN SUNLIGHT BEFORE USE TO IGNITE THE GLOW EFFECT Only use with water-based lubricant. Clean with anti-bacterial soap and water. Sila-Flex is a premium, phthalate-free hybrid silicone with an ultra smooth and soft finish. durable, unscented and extra stretch, while retaining the original shape.