SainSonic Rainbow Series 3D Active Rechargeable Shutter Glasses for Mitsubishi, Samsung, Acer, BenQ Improved Design: Portable, Light Weight and Comfortable for long time wearing. Better Viewing: Wider vision making the viewing experience Superior. Green consumption: Recharge with micro USB cable.3 hours recharging provides 50 hours operation. Easy Operating: Simple One Button Operation with Auto Shut Off, detailed user manual attached. Come with original 1-year warranty backed by SainStore, 24*7 Email Support, But with confidence.