Groove Life - Groove Ring The Worlds First Breathable Silicone Ring Original (Midnight Black/Blaze Orange) (Size 9) Breathable Design * Patent Pending * Medical Grade Silicone Groove is also non porous, non conductive, heat resistant, and hypoallergenic. * Width: 8mm or 5/16" + - * Thickness: 2mm or 3/32" + - Weightless Wedding Band and Accessory, Safe For Exercise, Weight Lifting, Training, Yoga, Hunting, Fishing, Hiking, Rock Climbing, Sports, Mechanics, Construction, Cleaning, Etc. Never have to take it off! With the ingenious groove design feel free to go about your daily activities without a worry or discomfort IMPORTANT: Groove is designed to be worn snug to your finger. Even if you know your size please re-measure.