Thru Glass Intercom-LI-ION Battery Comes with LI-ION Battery Pack for Approx. 10-12 Hours Duty Time and Gooseneck Microphone. Today's security and isolation booths and ticket booths are often the best step you can take to protect your employees. But do they protect and also help maintain your very important good will? Not if clerks and customers have to shout and growl and repeat themselves to be heard or understood. The Alpha Communications® / Haven SC-100L unit is a 2-way, hands-free audio system that provides high-quality personal communication between people separated by security or isolation barriers. It is a widely used system in the U.S., and around the world.