Samsung VERIZON Gear S3 CLASSIC Quick Reference Manual page 4

Setting up your Gear S3
Your Gear S3 already has a SIM card
installed.
Step 1. Charge your Gear S3
Before turning on your Gear S3, charge
it fully.
Wireless charger dock
NOTE: Your Gear S3 is equipped with a
nonremovable SIM card. You should never attempt
to open or disassemble your Gear S3. Doing so may
cause damage that voids your warranty.