ACCMOR 3pcs Wristbands with Metal Clasps for Fitbit Flex / Fitbit Flex Bracelet Sport Arm Bands (No Tracker, Replacement Bands Only) & 3pcs Silicon Fastener Ring For Free The Fitbit accessory is a one size fits most wrists, Free size that adjust by the button site. High quality and Replacement for lost or damaged Bands. Material: TPE+TPU. Materials do not harm human skin, environmental, safety, not allergic, do not harm human skin. The Bands feature a top window cutout that reveals the device LED lights The Fitbit accessory band is specifically designed for the Fitbit Flex. Comfortable for sporting time, Look good no matter what you are wearing Size reference: the super soft band is one size design. Adjustable from 162 mm/ 5.9 inches to 224 mm/ 8.27 inches.