I have yet to use one but I think they would be a good aid for getting them to come in when calling maybe preventing them from hanging up. Just a little more money than I want to spend at the current moment in my long list of items I would like to have
One of the most important pieces of equipment that you will take hunting is a good quality pair of optics and they take some care to give you the performance that you want. So here are a few tips.
Use some alcohol and cheese cloth to clean the lenses. I will usually pick up an extra cleaning kit from my optician when I have my eyes examined.
Don't touch the lens with your fingers. If there is a stick or a bug on them blow it off.
Use the lens covers. They are there...