Knot Theory Silicone Ring for Men – Mountain Wave Forest Engraved – 8mm Bandwidth Breathable Comfortable Fit Color: Black Mountain https://www.amazon.co.jp/gp/product/B097BG673C 【Stand Out with a Handmade Ring】Not your average mass-produced rubber wedding band. Knot Theory rings are carefully engraved by a passionate team in Canada. 【Perfect Fit Guaranteed】We guarantee a perfect fit and offer a risk-free way to get the perfect fit for your favorite ring. 【No Pinching for an Active Lifestyle】No pinching, calluses, or rashes. Keep your formal wedding ring at home and avoid scratches. For those who love to travel, go to the gym, play sports, music, cook, and enjoy the outdoors. 【Top Grade Silicone + Breathable Design】Made of flexible and durable food-grade silicone and metal-free pigments. The curved, smooth inner wall enhances airflow without the lines of grooves that trap moisture. Ergonomic design prevents finger muffin top. Looks great and feels great. 【Maximum Safety + Comfort】You can safely wear your ring at work or while pursuing your hobbies. Provides maximum comfort with a true comfort fit (curved inner wall). It conforms to your hand even if your fingers swell and keeps you comfortable.