http://www.amazon.com/Sena-SPH10-10-Bluetooth-Headset-Intercom/dp/B0087NB2OU/ref=sr_1_8?s=automotive&ie=UTF8&qid=1424452522&sr=1-8&keywords=sena+smh10

They were pricy but work great. I now consider them a safety feature not a cutesy "marriage saver."

We've used them for one full season without difficulty. I go the the bow and my wife can hear me in very normal conversational tone as I instruct the boat movement when deploying and retrieving the anchor. We've used them in fog when one of us is below looking at the PC chartplotter or doing other stuff and the other in the cockpit. We've used then in coming alongside unfamiliar docks.
We never have had any problem hearing outside persons talking in normal tones so issues of being cut of from others sounds haven't risen .
They recharge with a USB cable to any cigarette type 12v outlet like a Ipad or Iphone of from your PC.
I've made up a quick index card with the basic commands to interface them to each other so I dont have to go to the manual every time--that's a good thing until you get familiar with them because when you want to use them you don;t want a half hour fumble to get them paired to each other.
I've never used it but you can bluetooth them to cell phones and a radio, as well