Are you looking for a replacement silicone watch strap for your Fitbit Charge 4? The Fitbit Charge 4 Silicone Strap Frost White Size S is made for this watch and fits seamlessly. It's water-resistant and sweat proof. Feel free to exercise with it! You can easily clean the strap after a workout. Size S is suitable for a wrist circumference of 14 - 18cm.