Circle Smart Bike Brake Tail Light

Great tail light! I am four years n with this light and I’m ordering more only because I love it! Looks great on the bike and works flawlessly! Easy to turn on while riding. Holds a charge very well! Bright! Tucked away under the seat! Super solid mount. Better than any other bike mounted rail light I have used. Not what it needs to be and no more. Perfect design. Cheers! Buy some while you can!

This is simply the best bike taillight I’ve ever used. Most other tail lights on the market are cheap flimsy plastic pieces of junk. In contrast, this is solid aluminum housing with a bright light and an impressively battery life. I don’t have to charge it for weeks and I ride 5 to 10 miles every single day. The absolute best part is it turns on by itself with when you start riding and the brake light sensors accurate and actually turn on when you are breaking. This will be the last tail light you will ever buy.

This is a very nice rear cycling blinker with excellent battery life. I originally bought this item two years ago. Just replaced it after a battery failure by buying the same unit. I ride pretty much every day, weather permitting, so the two years of reliable performance was, in my opinion, very good. It is easy to mount, easy to take on and off to charge, and is very visible.

Update: Do not use the auto on/off feature it is unsafe. I used it in the early evening and it sensed enough light to shut off the light. This means the light could be disabled at dusk or dawn when you think it is on which is obviously dangerous. So you cannot use the first 2 modes since they have auto on/off. The light could also be on during part of your ride and off during the other part depending on the level of ambient light it senses. I also noticed after a few months that the two bracket screws loosened a little so make sure to check on those or use some light loctite. Note on battery life: if you use the highest brightness and solid mode you will get much lower run time, I only got about 8-10 hours. Fast blink is good though around 25 hours. ----- Initial impressions: light has good brightness at night almost blinding up close, but only just adequate for daytime visibility. Annoying restrictions limit how you use the modes. For example, slow blink and breathing mode must use auto on/off and the light gets disabled during the daytime. Fast blink and solid mode cannot use auto on/off but do not turn off during the daytime. I only use fast blink or solid mode which do not use auto on/off and stay on day or night. All modes still allow the light to brighten while braking and it's sensitive and actually works very well. Just touching the brakes slightly will brighten the light quickly, it almost feels like the brake lights on a car. However, it is frustrating that the light can only get very bright like this momentarily when braking. The brightness while braking would be perfect if it was allowed as the highest brightness but that is not possible. --- The auto on/off is too fast and shuts off after about 20 seconds of no movement. This could be bad at night if your light is constantly turning off when waiting at a standstill for longer than 20 seconds. Also you have to trust that the auto on feature is working properly otherwise the light might be off when you are riding. note: the instructions are unclear and don't explain that you can change the three brightness levels by holding the button while in solid light mode. The only setting I found useful was the highest and the other two settings are too dim. ---- These are just the issues I noticed but otherwise it is built quite well and appears solidly attached to the metal seatrail mount. If you don't mind being limited to just the fast blink and solid modes so that the light can be on at all times then it is a great rear light. One tip for mounting to the seatrail, you can mount the seatrail hanger on top or below the seatrail. This will adjust how high or low the light sits beneath your seat by about an inch or so. Mounting the light higher tucks it in better but it is slightly less visible than mounting it lower.

Added this light to the back of a Propel Endeavor S - it was recommended by an Endeavor Pro owner/rider. It's fancy no doubt.. the modes are well balanced to a ride's needs. Very nice touch to have 4 tiny tiny tiny lights inside the red ring as a battery gauge. The main feature that makes this little guy shine -- the brake sensor -- and it does it very well from what I was told when driving past friendships (bc I can't actually see the back of the board while riding) - Built quality -- it's solid.. very nice.. personally, I think devices like these should have bumpers.. this is the type of tech/gear that inevitably will take inconsistent handling, some abuse while removing to charge - then possibly sits in a basket along other smaller gadgets till it needs to go back on the board/bike.. but ehh - it produces a very nice consistent red light - it performs as describe... and I really enjoy having it on the board while I ride. Hope this helps... #Recommend

Great little light that is bright and easy to mount. All features have great battery life and I love the braking and auto off features. Since I am not buying this for a bicycle, but for the wheelchair used by a 90 year old relative, the one touch turn on is very literally a life saver. Charge seems to hold well. My only complaint is a little unfair: since this attaches to a wheelchair the interface is easy enough for a 90 year old with somewhat diminished capacity, but having to remove the light from it's retaining strap to charge the unit will be impossible. Fortunately the battery will last a while. (Dear entrepreneurs - PLEASE design a lighting system designed to fit wheelchairs, walkers , scooters, etc. that can be easily operated, mounted, and understood. It shouldn't cost 3x as much as a bicycle light! Amazing there are almost no examples in a world where everything else is available at fingertips. And spare me the lectures. Let's see YOU try to keep a strong willed veteran out of his chair and off the sidewalks at night. Good luck! ) Why in the world does Amazon want me to rate the 'thickness'? Stupid bots.

Product works well, has good battery life and functions well. Happy with my purchase and would buy again. Safety on the roads is a layered and multilevel for me and my braking rear light has improved my visibility on the road.

Muy buen accesorio, y la batería muy durable

bonne qualitee

Well worth it - light on auto setting last a month with out charging - riding upto 1 hour per day in twilight

C'est une excellente petite lumière, éclaire bien, solide, et ça principal qualité elle éclaire plus fort quand on freine. Je me suis gardé une étoile du fait que j'aurais apprécié que cette lumière sur le mode lent, et sur respiration puisse allumé en plein jour. Je la recommande vivement.