Yousave Accessories Compatible Straps For Fitbit Charge 3, Fitbit Charge 4 Strap for Women and Men, Silicone Fitbit Charge 3 Wristband, Sport Wrist Strap for the Fitbit Charge 3 and 4 -
Amazon.com: Fitbit Charge 3 bands
How to Change a Fitbit Charge 3 Strap by Yousave Accessories - Replacement Wrist Band Tutorial - YouTube