Used as security pants greenhouses. There are 4 red LEDs. You have to press the "OI" button visible in the photo. 2 modes (in tripping order): -Clignotant (All simultaneously lights) -All Lights on The battery is hidden in a pocket in the black part (back). It is "LITHIUM BATTERY CR2032 3V (button cell)" manufacture "CHN", so Chinese, I think. There is a little phrase in Japanese that says "LITHIUM BATTERY". 3M is a US company famous. The pouch containing the battery is a little tinkering. Difficult to extract it. Very good reflectivity. Very good visibility LEDs. With that hope that motorists increasingly barbarous and savage are a little more attention to the cyclist.
