Compatibility: This replacement band is only compatible with Amazfit T-Rex and T-Rex Pro (not compatible with T-Rex 2, T-Rex 3 and T-Rex Ultra). Note: Smartwatch not included. Premium Material: Made of durable and soft silicone material, the sport band is lightweight, breathable, waterproof, sweatproof, skin-friendly and prevents skin allergies. It is very comfortable for both daily wear and outdoor activities. Easy to Install: The T-Rex band comes with two screwdrivers to make installation easy and convenient. Simply unscrew one side. Wrist Size: The T-Rex Pro band is adjustable and fits wrists from 5.5-8.5 inches (140-216 mm). It features a classic pin buckle that holds the band securely in place. Multiple Colors: Personalize your T-Rex with these beautiful bands to suit your different moods and outfits. They look great on both men and women. If you have any questions about silicone watch bands, please contact us.