YABER Y31 home projector adopts an advanced german LED light source, high-quality materials, and a delicate manufacturing process. It delivers a bright large-screen with fantastic image clarity, outstanding color accuracy, and incredibly sharp image detail to both homes and businesses. The biggest feature is the y31's innovative 4D Keystone Correction ( 50 for horizontal and vertical correction), Auto Vertical Correction, One-Click Restore, and one-click to Brighten function which is not possible on other product. Despite the high price, some customers Y31 projector's chip consists of tens of thousands of reflective lenses, each lens is quickly switched every second to render 1080P full HD picture. 7000 lumens brightness significantly provides over 60+% brightness than other mini projectors, which serves your eyes better. HiFi Stereo Audio Performance Built-in dual stereo speakers (3W) with SRS Sound System. With double clear sound quality, the powerful speakers give you an immersive experience. HiFi stereo audio performance - with dual speakers, 3W, with gragra version intelligent temperature control technology, improves heat dissipation of the projector. A double-Sided cooling system enhances the heat spread of Y31 - 2x more powerful than ordinary LED projectors. It decreases at least 30-40% noise compared to the normal projection on the market, and you can also change the fan speed to reduce noise by the remote control. Bring your Smartphone or MacBook to the big screen. Notes on linking external devices: the y31 projector includes many inputs: 2 x HDMI if you want to play AVI, MKV, WMV video, connect the computer to the projector for playback. But the device cannot play 4k videos by connecting the smartphones or laptop directly, but cannot support play4k format videos unless you connect a USB stick or 4x devices. 4. Due to the technical bottleneck of 1080p projectors.