Authentic Avegant Glyph VR video headsets, come with Retinal Imaging Technology, it is the most advanced viewing experience for wearable displays. +1 to -7 diopter adjustment range makes most Shortsighted and Farsighted people enjoy clear images without wearing glasses; Built in 720p HDMI display screen, supports all HDMI output devices, such as smart TV, PS4, smart phone (need HDMI hub adapter), and you do not need to install your smart phone on; Lightweight so that you may not feel uncomfortable with such bearing on your head. Package comes with an external head strap to make it more stable on your head; Unlike other VR glasses, you can pay attention to surrounding without taking this Glyph off, just move down your sight and you will see scene around you. It can also be used as headphones by connection cellphone via audio cable. If you want to have a rest, just hang the VR on your neck like a headset; Built in a charging and discharging battery with 2060mAh battery, working time is up to 4 hours (theoretically), supporting you finish watching one to two movies. You can also use it while charging, good private theater.