Waterproof Multi Sports Modes With Charging Case. 1> Daily activities: Step count, distance, calorie calculation. Charging mode: Magnetic attraction. Dust Proof & Waterproof Level: 1ATM. Ring size (mm) : No.717.4mm, No.818.2mm, No.919, No.10 19.9mm, No. 11 20.7mm, No.12 21.5mm, No.13 22.3mm.
eBay