ROCKBROS Smart Bike Tail Light Brake Sensing Bicycle Rear Lights USB Rechargeable IPX6 Waterproof Bright LED Bike Light 260mah Cycling Safety Road BikeTaillight Accessories 4 Modes

Great price for an auto on light. It's bright, I don't want to look at it directly. I was ready to spend more but I'm happy I didn't.

I really like this tail light. It has served me well and very intuitive.

I've had this little light for about 5 months now and it's been great. It has several different modes to select from and it has a really neat feature where it will light up solid when braking, just like when braking in a car, so it helps people to know you're putting you're actually putting your brakes on and slowing down/stopping. Charge seems to last a while and I like that it's USB-C. I ended up putting a dab of silicone caulk on the back of the little rubber shim to keep it in place and not get lost as I could see that happening. I do recommend!

First the best parts- Small form factor & its USB-C rechargeable.- Auto shut off & also auto turn-on modes lights up when the bike starts moving again!- Break Light! - the accelerometer based brightness control is good if the bike stops or moves backwards it glows!- two types of mounts ( saddle mounts) with ample cable ties useful esp., for bikes with aero seatposts and saddle post mount for circular saddle posts only (32mm max )ConsThe saddle post rubber gets loosely attached to the holder although it gets sandwiched between the post and the holder after install it can easily get lost if you were to de-install it say, during the bike washes. I think , no harm using CA glue( superglue) to fix it to the holder permanently.The cable is too short and useless use your stand usb-c phone cable

Honestly, I've struggled with back red lights. Mostly, with how they attach. They are either simple elastic loops (that fall off or get stolen) or they are super-specific mounting systems that only work if your bike doesn't have any complications at all (like baskets or kid seats). This seems like a pretty good option BUT I would be pleased if it had more mounting options.

Surprisingly good for the price: very bright, battery life on a kids bike is enough to keep it unplugged for weeks being used for school commute, 15-20 minutes a day, even during freezing weather and unheated garage storage.Acceleration sensor may be a bit too sensitive, but I'd better prefer to have a brake false positives than a missed braking.Note that auto-off doesn't work in all the modes, check guides carefully.

fantastic, mounts right on the seat rails out of the way

This is a very nice affordable rear bike light. It does have four modes, but only the first two work with the brake light function.I do like the brake light function.Another plus is the use of USB connectors. The USB C is becoming more universal.Just another way to add additional safety to uour rides.