The Nomad Sport Strap is crafted entirely from durable LSR silicone, a naturally biocompatible, antimicrobial, and hypoallergenic material that provides a soft, safe, and comfortable wear around the wrist. Highlights include being waterproof, made from vulcanized LSR silicone, hypoallergenic, and biocompatible. The strap is compatible with Apple Watches of 45mm, 44mm, and 42mm, designed for Apple Watch Ultra & Ultra 2, Series 1-9, and earlier Apple Watch SE models. Features a 72-hour salt spray test as specified in ASTM B117, ROHS. Compatible with Apple Watch 45mm, 49mm, 42mm, and 44mm.