Two Adjustable Sizes: Large is for 6.7"-8.1" wrist, small is for 5.5"- 6.7" wrist. Breathable Wearing Experience: These bands for Fitbit Charge 2 HR are made from soft silicone, designing multiple air holes make your wrist ventilated and comfortable, waterproof and sweatproof. No Worry about Falling off: These replacement wristbands for Fitbit Charge 2 design with metal clasps on both ends, which locks onto the charge 2 precisely and securely. Easy to Replace - Simple to install and take off, no tool required. Abundant colors are available for men, women, adults and kids to choose. Fit your daily style & any occasion. After-sale Service - For any problems, please contact us, we will give you a perfect solution within 24 hours. POY Replacement Bands Compatible for Fitbit Charge 2 Adjustable Breathable Wristbands with Air Holes Straps - B286UBJV1