EBUYFIRE Smart Bike Tail Light, USB Rechargeable Ultra Bright Rear LED Bicycle Light, Auto On/Off, IPX6 Waterproof, Black, 1 Pack, Automatic, Bicycle

First time I saw a similar product advertised was on FB. And with FB ads, I usually have a load of skeptism towards them because fulfillment is usually an issue and the comments sections, if you dig past the fake positives, is usually littered with unhappy customers who never received the product. So when I saw this product on Amazon, I was also skeptical but was assured that it's at least on Amazon and I'll most likely receive the product at least.The product arrived as quickly as anyone in CONUS can expect (2-3days) and I was immediately impressed. The housing of the lights and mount is made of anodized aluminum and feel rock solid. Buttons have a nice tactile feel to them. The packaging wasn't anything impressive but I don't care about something that's going in the bin. It provided several ways to mount the light, primarily seat post and saddle rails. I preferred saddle rails as I usually carry my spare in cycling jersey and I like the high position of the light, which makes it more visible.Battery life on the light is sufficiently long for my purposes, although I haven't done long rides at night to find out. What I could say is I can go several rides before I have to charge it. It would be nice to have some kind of battery indication. I do find myself reaching for the charger regardless of how much battery is left, which is not great for batteries.The light has several modes that you can cycle through with the single switch in the front. There's also a toggle switch in the back from "Auto" to "Manual." I've never been too sure what it really means; I think it's controls Auto/Manual on-off by motion sensor. I've left it in manual so the light doesn't turn on as I move about the apartment. When I ride, I can just toggle it to <Auto>, screw it onto the bike and let it do its thing.The light itself has three modes: constant, flashing, and pulsing. Each mode is what the light looks like when there is no acceleration in any direction (deceleration is also a type of acceleration in the world of physics). When acceleration or deceleration is detected, the light immediately turns solid + bright to act like a brake light. The accelerometer is very sensitive and will be very effective to indicate your change of speed. When riding solo on the road, this will be invaluable in informing drivers and other rides what's going on with my bike. I can also see this light being very helpful for group rides as it helps to get the riders behind's attention. Only potential downside is if it's *too* sensitives and anytime I back off the pedal it lights up as if i'm jamming on the brakes, which could take a bit of getting used to. I haven't taken this on a large MAMIL group ride so I don't know. Whenever I get opportunity to do that I and get some feedbacks, I will come back and update the review. That shouldn't stop you from buying this light though, imo. It's an amazing product and worth every penny.Now, let's talk customer service.I liked these lights so much I actually bought two. And a few weeks ago, however, I realized I had misplaced the saddle rail mount. I might've thrown it out along with my old broken saddle carelessly or whatever. I dug up my Amazon order from almost 6 mo ago and emailed the seller asking if they could sell me a spare part - after all it was my fault I lost this. The seller got back to me within 24h and *offered* to send me a brand new product for free! No questions asked! Where do you find customer service like this?! These Chinese sellers are so amazing I'm completely floored. We're talking about a $20 bike light, not a $50k Rolex with super high margins... This is just unparalleled and makes me feel like there's never been a better time to be a consumer.If you're in the market for a bike light and you think this might suit your need, take a punt with $20 and go for it. You won't be disappointed. And even if you are, it's $20 bucks and if you really want it back, I'm sure you can get a refund. It's a damn good product from a damn good seller. Best of Amazon.

This thing works excellently. For the price, i was expecting mediocre results. This has actually a pretty good build quality. The mounting plate is aluminum or metal of some time too. No fuss to install, and very attractive and discreet once on the bike. Very bright in daylight condutions too, which surprised me. Brake light function is spot-on. Gonna get a few more for all my other bikes.

Was hopeful this would be an ideal tail light for the features it has. Unfortunately, this one was dim, the brake light feature was slow to respond, really didn't last very long. Battery died after less than an hour into a ride.The vendor was super supportive so 1 star back due to their stellar responsiveness.I've seen that this can be a very useful tail light. The replacement one is much brighter, the brake light feature is quick and seems to be doing fine. So, 3 stars overall, the first one being a 1 star, second one I'll give it a 4 (for now)

Awesome addition for riding at night. Works well during the day also. Received compliments on the brake light feature. I ride an hour a day and the battery so far has lasted a week before needing a charge.

All a bike light needs to do is aid visibility and stay on. I started to notice after finishing each ride, I never have to turn the light off, because it's already off. It makes me wonder how long ago it stopped blinking and how visible or safe I really was during that time. This 'smart' light turns itself off after one hour, sometimes shorter. I verified this by timing it with my watch while stationary. Unfortunately I determined this after my return window had closed. It seems to be a pretty well constructed and bright light otherwise. I with it had no 'smart' functions and simply had a blink mode that didn't stop until turned off.

I love the slow-pulse mode for visibility from behind, and the motion sensor brake light feature. This light mounts unobtrusively under the seat, and starts to pulse in Auto mode as soon as the bike moves. The 'brake light' feature seems to work well according to my riding buddy, and I went over 50 miles on my last charge before recharging the unit just to be on the safe side. Excellent purchase!

Very easy setup, and install. Works as described. Really liked the brake light feature.Will be buying another!!!

Although the product name is not mentioned by this seller, the light is the X100 Smart Light and comes packaged with this branding. It's compact and solid with a small auto / manual switch on the backside. It threads onto the bike mount and you unscrew it to recharge it.I read the reviews before buying and as a result I use it only in the manual mode. This way I'm not relying on it to detect movement. If I stop for any length of time I simply turn it off as with any of my older lights. What I was attracted to is the brake sensor in case I'm riding with someone. For the way I use it I find it works as advertised.My one complaint is why I give this product 3 stars instead of 4 or 5. It comes packaged with a seat mount and 4 zip ties. This mount prevents you from mounting a rear seat bag and you have to move the seat back to make room for the zip ties. I position my seat all the way forward.There is a solution and it's shown in the instructions that come with the light. There is a seatpost mount available separately for $8.99. Find it here: https://www.amazon.com/gp/product/B07GWDLH1X/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1I don't understand why they don't package it with this mount and charge the difference in price. The seat mount is unusable for most cyclists as other reviewers have stated. I ordered the post mount and I'm good to go!