I have the Walkers $140 in ear. The batteries are a type which i have never used. Basically, you peel a little label off, and they activate. From then on, they work for "80 hours," but there is no saving the battery by turning the device off. They simply go-go-go until they poop out.
One set of batteries lasts a whole weekend of shooting birds, or on the range for me. Next weekend, need new batteries.
I bought a big pack of batteries thru Amazon or Walmart for $20 or so.
The units work fine. Sound quality is pretty crappy, like an old-school walktie-talkie or the like, but you can have normal conversations, and they do suppress the report of gunfire.
Rick, my niece is a Doctor of audiology, and told me that testing shows hearing aid batteries will last ~ 10% longer if opened - then not put into use for 7 - 10 minutes. JFYI.
