Product description Lens material: liquid crystal Color: Black Quantity: 1pc, 2pcs Package content: 1pcs/2pcs * 3D glasses 1.Designed for 3D projector High-end 3D Glasses use as their sync method, no Emitter required can quickly works with projectors. 2. Strong Compatibility Our 3D active glasses is compatible with Optoma/Acer/Vivitek/Panasonic/Dell/Viewsonic/LG/Samsung/Mitsubishi 3D projectors. (Note: The 3D glasses isn't compatible with Epson, Sony Bluetooth Projectors, also can't work with TVs). 3. Super Fast 144Hz Refresh Rate 3D glasses adopts the newest active shutter technology, next generation super fast 144Hz refresh rate, High definition, no ghosting images, no flickering, generates a better brightness, sharpness and contrast, provides a great 3D viewing experience for you 4.Long Lasting Battery The 3D glasses comes with built-in high capacity rechargeable battery, continuous working 60 hours after fully charged with USB , standby time 180 days. 5.High quality Materials & Lightweight & Comfortable The 3D active shutter glasses is made of high-quality super Soft black rubberized, much more comfortable than lower quality standard plastic 3D glasses; comfortable to wear for a long time.