CDC® Bike tail Light - Waterproof Rear Bike LED - Best & Brightest - Small & Rugged - Mount w/out tools - Road, Racing & Mountain - Batteries Included - Fits ALL Bicycles, Trikes, Scooters

This has been a problem and I've had to replace it. First the good: when it has fresh batteries and is working, it is bright, easy to attach to most things with enough thickness to them (the attaching strap is quite stretchy and overall very good), and the operating modes (full on, quick flash, slow flash) are fine.However, the fatal flaw with the one I have is that if given a sharp knock it switches off. Perhaps this is a flawed unit, but it's a dangerous problem because it's not easily observable if you're not looking for it. It's sufficiently sensitive that it will turn off if you cycle over a particularly rough bump in the road. Mostly it doesn't, but maybe once a week it does. So cycling with only this back light makes me a nervous wreck, constantly turning around to check whether it's still on after every bump.The mode selector (pushing on the red LED cover) is also imprecise. It clicks more than once when you push it in and will sometimes skip forward a few modes. So you can't turn it on and off unobserved (e.g. on the back of your helmet) and trust that you've selected the right mode, or even that it's on at all.I now use a replacement as my main rear light and have attached this to my helmet where it's more insulated from bumps. Since it takes replaceable batteries, I intend to use it mainly as a backup from now on.Two stars because when it works it's good, and I like the attachment strap.

These lights are bright and compact and are sturdily made. You can attach them with the rubber strip provided or you can easily remove it and make an attachment using the screw that fixes it. Be sure to remove the insulating shim that protects the battery contact. As they are so cheap and light I would recommend fitting two so that you have a reserve when the battery fails. Lithium cells tend to die without much warning.

Use a pair of these on my sons bike trailer, being for the trailer i didnt want to spend the earth, was sceptical at first especially when i noted the screw in the back, however they are bright and screw apart seem well made. Perfect for the situation i need them for, only reason i havent yet given 5 stars is due to not knowing how long they will last. Well worth the minimal cost though.

Great bikelight which works off two button batteries. Three clicks will hange from on, flashing and slow flash. I bought two just so I can easily change them around when the battery does go. Bright and easy to fit.

Received this item today but sadly it did not work.i even replaced the batteries thinking that was the problem but alas was not.no point sending it back as will cost too much to do so.i will just put this down too a very disappointing avent.not happy

Nice bright light. But battery life isn’t great and after a couple of recent wet rides light has started to flicker, sometimes switch off, so doesn’t appear to be fully water proof.

I love this product, I have two of them, LED battery powered they last for ages.

Good light