Portland Design Works

Gravity 80 USB Auto Tail Light

If your commute takes you winding through the cities, or your group rides can get a bit crowded and chaotic when it comes to stop lights, throw the Portland Design Works Gravity 80 USB Auto Tail Light on your ride. This handy light doesn't just offer you the reassurance of a flashing or steady tail light, but it also adds a built in accelerometer to the mix. The accelerometer on the Gravity 80 registers when you're accelerating or decelerating, illuminating a second LED that shines at a brighter 100-lumens when you brake, so motorists and fellow cyclists get an alert to let them know what's going on ahead. It has two modes, flashing 80-lumen, or solid 20-lumen, depending on your riding needs, both work with the brake light, and it can be mounted either vertically, or horizontally to your seatpost or seatstay.

When you're getting ready to hit the road, Portland Design Works recommends calibrating the light first — don't worry, it's not a daunting task. Simply install your light on its mount before powering it on, and hold it still for one-second before hitting that power button, then you're good to go. The light will be ready to roll for up to 12-hours on solid, or 30-hours on flash, and can be recharged at your buddy's house or the office using a compact Micro USB charging cord.