What Our Gearhead(R) Experts Are Saying:"I started running the Lezyne E-Bike Z-Mark Super Bright StVZO Ai Alert Rear on my commuter and the Ai Alert mode is the kind of feature that makes you wonder how you rode in traffic without it. The automatic deceleration detection fires before I even think about it, which is exactly what you want when there are cars close behind."City riding asks a lot of the people around you, and the more clearly you can communicate your intentions, the safer everyone is. The Lezyne E-Bike Z-Mark Super Bright StVZO Ai Alert Rear brings smart brake-sensing technology to your e-bike's rear lighting, automatically detecting deceleration and triggering a 35 lumen, 10 LED Ai Alert signal that tells the rider or driver behind you that you are slowing down before they have to figure it out themselves. In dense traffic or on fast commutes, that split second of advance warning is the kind of thing that matters. The Z-Mark pairs a German StVZO Z-reflector optimized lens with wide angle optics for broad visibility in standard running mode, and draws cleanly from your e-bike system via a 6-12V compatible input. At just 48g, the composite matrix rack mounting system keeps installation clean and low-profile, with 50mm and 80mm mount spacing covering a wide range of rack configurations. IPX7 waterproofing and stainless allen key hardware mean this light is built to stay on the bike and keep working through whatever the commute throws at it.