Auto-detects which brand of 3D TV in use USB Rechargeable built-in battery Auto power off function to save battery life 3 Hours of charging gives 50 hours of use Interchangeable nose pads for a perfect fit Soft carry case for easy transportation Lightweight and comfortable active shutter 3D glasses to provide a perfect vivid and dynamic 3D image experience. These 3D glasses will last up to 50 hours of viewing on one 3 hour charge due to the built in rechargeable battery. They also come with 3 different sized nose pads to ensure a comfortable fit. They also come with a cloth bag for better storage and transportation. With a simple change of frequency these glasses can be used with an LG Sony or Samsung 3D TV. Making these 3D glasses Universal.