I think you will be hard pressed to find some that will work all over the ship. There are dead spots on all cruise ships. The good news is that they will work in most places. Everytime we cruise we take ours. The 8 mile cobras are a good radio I think they only put out 2 amps. I use the Motorola 25 mile 5 amp radios. It's a little more power to help get you through the dead spots. It doesn't always happen though. Try Best Buy .Target or wal-mart.