Pocket Size: 38mm x 38mm x 10mm Adjustable brightness: high/middle/low Rechargeable battery inside, no need to drain your device's battery It can be used as a simple flashlight or a small emergency lamp, taking photo is no longer an issue at night No red eye: easily have natural flash,let you take better photos it is a multi feature very small and handy speedlite. Compatible with Apple iPhone 6 Plus/6/5/5S/5C/4/4S, iPad Air 2/1, iPad 4/3/2, iPad Mini 3/2/1, Samsung Galaxy S6/S5/S4/S3/S5 Mini/S4 Mini, Galaxy Note 4/3/2/Edge, LG tribute, G3/G2, optimus l70/l90/G Pro, Lenovo S8 S898T/A850, Sony Xperia Z3/Z2/Z1/Z1 Compact, Huawei G610/Ascend Mate 7/2/P7/P6/Honor 6, Google Nexus 7/6/5, BlackBerry Z10