The Fitbit Ace 2 classic band is made of a flexible elastomer material similar to that used in many sport watches and includes a plastic buckle.
Fitbit Ace 2 is swimproof, meaning it's water resistant to 50 metres. After swimming or getting the band wet, we recommend drying off the band because, as with any wearable device, it's best for your child's skin if the band is clean and dry. We do not recommend wearing Fitbit Ace 2 in a hot tub or sauna. See www.fitbit.com/productcare for more details.
If your child gets the Fitbit Ace 2 band wet or sweats in it, remove and completely dry the band before they put it back on. Make sure kids take the band off every now and then and regularly clean the band and wrist area around it with water. Learn more.