Good to know- With 4500 lumens everyone will see your presentation clearly even without a pitch-black room- Acer LumiSense technology and wall-colour compensation mean there's no need to use a projection screen- A range of inputs, including HDMI, VGA and composite video, let you connect virtually any device- There's a built-in speaker, and you can hook up a sound system using the 3.5 mm jack- It's got an impressive lamp life of 6000 hours - or 15,000 hours in extreme eco mode - so you'll get years of use