Quote Originally Posted by GLC1968 View Post
Now I'm wearing the Timex just for HRM and stopwatch features. It's a base model and it works great. I wear it on the swim for timing, but I don't use the chest strap. I was wearing the chest strap during my tri, but I never bothered to look if I had any HR data during that time period and I've since erased the session. I've heard that the coded Polar straps will work in water but none of the other makers do. I was not a swimmer when I had my Polar, so I can't say for certain.
I clicked on a few different models (not just the RS800cx) and Polar says:

Quote Originally Posted by Polar Website
Swimming with Polar RS800 / RS800CX

The running computer is water resistant. However, heart rate measurement does not work in water. You can use the running computer under water as a watch but it is not a diving instrument. To maintain water resistance, do not press the buttons of the running computer under water.
I might try mine in the pool and see how it goes. I have worn my other Polar through triathlons but never had the ability to go back in detail like I do now.