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Optoma BG-ZF2100GLS Active Shutter 3D-RF Glasses

Improved contrast and black level
Lightweight stylish design with interchangeable nose pieces for customized comfort
Always in sync - RF Radio Frequency based synchronization with 3D content
Rechargeable long-life Lithium polymer battery
Designed for use with Optoma projectors with 3D VESA output and synchronization system