This is going to be a short review buy this is a great bit of kit for swimming. Goes in your swim hat and can be set to bleep at a constant rate, to help time your stroke rate, or to beep on intervals, great for pacing.
Been using mine for a while in both ways. Has helped improve my flow and rhythm and is also great for pacing feedback in real-time.
Swimming times are back to near their best, today I had it beeping to pace me for a 1500 TT. I used to think I swam at a consistent speed but having the beep to keep on target is great.
Best bit of swim kit I have ever purchased!