Product Feature:1，Waterproof， can be use in rainy day. Also shockproof，no need to worry bump.2，5 super bright red LED， runs over 30 hours on constant or 60 hours on flashing.Your safety is always the first PRIORITY.3，Can be used according to demand， adjust the horizontal or vertical installation4，3 modes， flashing， constant， side to side.5，Easy to install and uninstall.Product Description: With 5 LED，brighter than regular taillight.Functions: flash-steady-chasing Suit for: Fits all bicycles Battery: 2 AAA batteries requiredDimensions: 110 x 40 x 20mm(approx) Color:redWeight:67gPackage includes:1*5 LED Long Taillight +1* Clamp