The Femto USB Drive Rear is a compact, super lightweight USB rechargeable LED cycling taillight. Its durable co-moulded construction is minimal and has an IPX7 water resistance rating. A versatile mounting strap quickly mounts to a variety of post sizes. Five output modes offer up to 5-lumens and the custom Wide Angle Optics lens provides well over 180° of visibility. The Femto USB Rear can run for up to 15 hours and is easily rechargeable with the included Micro USB cable. A secure, threaded composite matrix cover keeps the USB port clean and sealed. The Femto USB is perfect for commuters and recreational riders looking for a simple and inexpensive way to add visibility. Key Features:Max Lumens: 5 lumensWeight: 23gMax Runtime: 15 hoursRecharge Time: 2.5 hoursColours: Black, Red, Blue or White