Review on Ultimate Safety: CXWXC Smart Bike Tail Lights - USB Rechargeable, Waterproof with Ultra Bright LED Brake Light for Cycling Riding by Ivan Brown

Tail light is large and very bright. It has multiple flashing patterns, but my favorite feature is the movement-sensing brake light function. Essentially when the light senses forward deceleration the LEDs will get 100% brighter to someone behind you, it looks like you're just "slamming on the brakes", which is exactly what I wanted. Big bumps or bumps can also trigger the brake light, so it's not ideal, but it's a great motion-based feature that doesn't require running wires or manually activating the brake light with a button on the steering wheel. It comes with detachable rubber. Harness attachment and a semi-permanent attachment under the seat secured with zips. One thing to remember: make sure you lock it in place. If you don't slide it all the way into the mount, bumps in the road could cause it to slide out. I lost one of these lights because it wasn't fully engaged.