Your YachtPhone service works in the continental United States and near shore waterways. Your YachtPhone service is supported by the leading GSM networks in the United States.
Your YachtPhone is tri-band GSM and is unlocked. Unlocked means you can use a SIM which can be obtained separately in other countries. Tri-band GSM means you can use the phone in nearly every country in the world, provided you have obtained separately a SIM compatible with networks in that country. The SIM provided by YachtPhone only provides service in the United States.
YachtPhone meets military spec IP-57 for a depth of 3 feet and a maximum duration of 30 minutes. Exceeding these limits may permanently damage the device. The warranty is valid only if these limits are observed and the instructions for maintaining the waterproofing are followed.