What Makes the PDW Gravity Plus the Smartest Tail Light Available? The PDW Gravity Plus USB Tail Light has a built-in accelerometer that actively monitors your speed and behavior while you ride. When the sensor detects braking or swerving, it automatically switches to a super-bright solid beam to alert following traffic before they realize you're slowing down. It's the closest thing to a brake light that a bike tail light has ever offered, and it runs on a USB-rechargeable battery that keeps the system maintenance-free. Setup requires a simple calibration routine: install on your bike before powering on, then hold still for one second after pressing the power button to let the accelerometer zero itself. After that it works automatically every ride. The Gravity Plus is a meaningful upgrade over passive blinky lights for urban riders, commuters, and road cyclists who share lanes with fast-moving traffic and want an active layer of protection behind them.
