this strap will fit a wrist 6.3 in to 8.25 in diameter.

SwatchMens Quartz Watch, Analog Display and Silicone Strap - GP403

SwatchMens Quartz Watch, Analog Display and Silicone Strap - GP403

Q: Does the back of the watch contain metal?

The back of the battery door does contain metal.

Q: Do you have to manually change the date on this watch?

The date needs to be manually set but it updates daily. We recommend setting the date in the AM as it changes every night at midnight. Also you will need to adjust the date from time to time as some months have 30 days, some have 31 and February has 28.