Femto USB Drive STVZOCompact, 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. Two output modes offer up to 5-lumens and the custom Wide Angle Optics lens provides up to 270° 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.Features: Max Lumens: 8 Weight: 23g Max Runtime: 8 hours Recharge Time: 2:30 hours