Black 21mm Natural Rubber Watch Strap with Pin Buckle A durable, comfortable replacement strap designed for watches with a 21mm lug width. Made from natural rubber with a moderate softness that balances comfort and durability. Adjustable length and a pin buckle closure make fit and wear simple. Key features Color: Black. Size: 21mm lug width. Material: natural rubber for a soft yet sturdy feel. Closure: Pin buckle for secure, adjustable fit. Construction: Compression molded for long lasting shape and strength. Fit: Easily adjustable length to accommodate most wrist sizes. Installation: Easy to insert and remove for quick strap changes. Why choose this strap Comfortable daily wear thanks to moderate softness and flexible material. Durable construction resists wear while keeping a neat, finished look. Simple, tool length adjustment and reliable pin buckle make it practical for everyday use. Compatibility and use Designed to or upgrade straps on any watch with a 21mm lug width. Ideal for replacing a worn strap, updating a watch appearance, or keeping a spare for travel. Practical applications Daily wear: comfortable for office and casual use. Active use: suitable for outdoor activities where a flexible, durable strap is preferred. Travel and backup: compact and easy to swap when a quick change is needed. Care tips Rinse with clean water and dry after heavy sweating or exposure to dirt. Store flat or laid out to avoid sharp bends that can stress the material. This 21mm black rubber strap offers a practical balance of comfort, durability, and easy fit for most watches with a matching lug width.