Portland Design Works | Gravity+ 100 USB Tail Light with Accelerometer

It is approaching 4 years of ownership. I ride on a very busy road, with this - I have two tail lights. This light although not as bright as some others has lasted while two others failed, one quit working and the second broke off its mount. My present second light mounts in the seat support system which gives a good light but requires charging at least 5 times as often as this light which is a nuisance. I recommend this light because my neighbor states he can see it at a great distance, the exceptional battery life (compared to three others) and the fact that it still works after nearly 4 years.

I ride 2500 miles a year on a BMC road bike.Dislike: Tried 2 different tail lights and could not get it to work consistently. When it works it is nice and bright. There is a brief calibration procedure you must do.Like: Company is great to work with. They offered a daybot model as replacement, this has three modes and is very bright. Bright mode is great when I cycle alone, there are 2 other modes that are good for group rides so you will not fry out the eyes of cyclist behind you. Charge is good for at least 5-6 hours which is 2 rides for me. Easy and fast to charge. I have used the frame mount and seat post mounts for 2 different road bikes.

Used less than a handful of times and won’t turn on, even when fully charged.

PDW was very helpful in handling an issue and quickly replaced a malfunctioning unit. I use this as a daytime running light. The light is bright and easy to use. I like the dual lights with flashing pattern that really gets your attention.

Checks all my boxes. Easy to get on the bike. Water proof. Rechargeable. Couldn't be happier as a regular commuter and group rider.

If you want quality and a strong design look no further

I really wanted to like the light. After using it for a few rides I had to return it.I feel that the thing that sets this light apart is the brake sensing part of it. Unfortunately that feature didn't work reliably. It did effectively sense me applying the brakes but it also sensed be hitting bumps and changes in inclination. In the end I would say that the light would stay lit solid as if it was sensing me braking during 30% of my ride. This led to excessive battery usage and the person riding behind me to disregard the light going solid. Definitely worked better than an old mercury switch would have but not reliable enough for the feature to be useful.Other than that I would say that how the mount attaches to the light could be better. Detaching the light from the mount requires two hands and I have had other lights (some from PDW) that I could easily detach with one hand.

The brake light doesn't activate when braking or swerving. I'm not sure if it's just mine that's broken, or none of them actually work as advertised. I bought it for the brake functionality. Without that, it's an expensive, sub-par tail light. There are only two modes: (1) solid, (2) flashing pattern. I wish there were a few other modes to choose from, like a slow, steady flash.EDIT: I returned it for a replacement, and the brake light works on the new one. So, minus one star for the inconvenience, and minus one star because I still wish it had more flash modes.