Bright 4,000 lumens and 22,000:1 contrast ratio produce razor-sharp images PC-free USB image viewer and office document reader Wireless presentations and images with HDCast Pro (USB Wi-Fi adapter included) USB display screen mirroring with iOS and Android devices LAN display via Ethernet with Windows and Mac OS X Auto keystone and four corner correction for robust installation Spectacular 100" 1080p image from inches away Enhance presentations and events with colorful and bright 4,000 lumens 1080p images from the Optoma EH340UST. Its 22,000:1 contrast ratio and ultra short throw ratio display sharp 100-inch images from inches away - perfect for space constrained environments such as small classrooms, meeting rooms, boardrooms and digital signage applications. A PC-free image viewer and document reader display office documents, PDFs and images from USB storage devices. HDCast Pro connectivity provides wireless screen mirroring with Android, Mac OS and Windows devices. LAN display supports up to 4 simultaneous computers while USB display mirrors Android and iOS devices. Four corner geometric correction allows flexible installations while robust input options include HDMI, VGA and RJ-45 for connectivity to a wide range of devices.