Radio

You don't just need it for safety, it's often the only way to be able to communicate with others on the water.

Most people around here are on channel 9.

Many people use ICOM M25. Mine is an Oricom MX500. I broke my first three pretty much straight away. Oricom replaced each one. My current one I've had for five years without a glitch. I now keep it in the PFD pocket instead of attached to the shoulder. I also only have to charge it once a year, which is quite impressive.