Sizes are equivalent to silicone bands from Apple
- 41mm , 40mm and 38mm S/M Size: Fits 5.1"-7.1" (130mm-180mm) wrist
- 41mm , 40mm and 38mm M/L Size: Fits 5.9"-7.9" (150mm-200mm) wrist
- 49mm , 45mm, 44mm and 42mm S/M Size: Fits 5.5"-7.5" (140mm-190mm) wrist
- 49mm, 45mm, 44mm & 42mm M/L Size: Fits 6.3"-8.3" (160mm-210mm) wrist