DAWAYA08 Bike Tire Valve Stem Light - LED Waterproof Bicycle Wheel Lights Neon Flashing Lamp Glow in The Dark Cool Safe Accessories, 1 Pack/ 2 Pack

Love these! I'm an urban bike commuter and have several light acoutrem on my bike. These lights are incredibly lightweight, very bright, and I love the design. Definitely add visibility. I like the auto turn off.My only negative comment is that they don't seem to be terribly well made, as the threading on the inside is a little dicey, but for how well they perform and how lightweight they are I would probably just buy more if they stopped working anytime soon. I've probably used them for a little over 5 hours so far and they're still going strong.

I really like these blue wheel lights. They make the ground glow kind of like those neon lights under cars, which looks awesome at night. I'm glad they screw on because they feel way more secure that way. I've never been a fan of those clip-on spoke lights, they just seem too easy to lose.These lights don't add any weight, so you don't even notice they're there when you're riding. I've been using them for about 10-15 hours, and they're still going strong. Honestly, even if they stopped working after a month, I'd just buy them again. Riding around at night with these lights makes me feel like I'm in a Tron movie, and it kinda makes me want to pedal faster to see the lights spin out.The only thing I'd wish for is more options, like maybe a solid blue line. But I get why they didn't do that – simpler is probably better for something that's spinning around your wheels for hours. It probably means there's less chance of something breaking inside. But really, that's just me nitpicking.Overall, these lights are a blast and make night rides way more fun. Plus, they help with visibility at night, which is a huge bonus.

The product is poorly designed. To install the batteries you have to open the battery compartment by unscrewing the unit. When you are unscrewing the unit you can see the plastic male threads flaking because of the metallic female threads. So now the plastic threads are worn from unscrewing the unit, you install the batteries, and now you try to screw the unit back together and the plastic threads don’t want to thread onto the metallic threads, then I finally got the unit screw together, and believe me when I tell you it took a lot of time and persistence because when I finally did get it screwed together but the unit would not work because of this little metal wire that needs to make contact with the battery and it would not, so I had to mess with that a bunch of times which also meant having to deal with the never ending worn and wearing plastic threads, at least thank goodness I didn’t have to completely unscrew the unit to mess with the contact wire thing. Well I finally got the unit to work by trial and error but I dread the day I have to change the batteries out, the plastic threads won’t survive another battery change out, then I had to be very careful screwing the unit onto my bike tire stem valve to not turn the unit screw thread because that would mess with the contact wire thing andthen it would be back to the drawing board. No quality control, and not user friendly need to go back to the drawing board on this one. But I must say now that I got it working and installed I love the way the unit lights up. I would love to purchase a second unit but it is poorly made and I would not want to have to hassle with another one.

I've taken the batteries out and reinstalled several times and can't get the lights to come on. I think they are defective. It's a shame because I really excited to use them!======Update - after fiddling with them for quite a while, I got the batteries to connect and they lit up. The problem is that the little batteries flip over when you drop them in, so you have to be really careful that they go into the tube in the correct direction. If you're thinking, wow, this girl is an idiot... trust me when I say it's harder than it looks.I agree with some other reviews that the plastic threads are less than ideal. You need to be careful when screwing the light back together after installing the batteries (which you might do 6 times before you get it right). The threads shed little pieces of plastic and you have to be gentle so as not to strip them completely. If you have a little tube of bike grease laying around, it wouldn't be the worst idea to add a dab to the threads.I used these on my presta valves on a 30 mile midnight ride in Boston and while I couldn't see them when riding, my friends said they were doing really cool things (changing into arrows at high speeds, etc.). They lasted the whole ride, which ended up being over 3 hours with all our stops and mechanicals. I also got a flat at mile 12 and had to take one of these off to replace the tube but when I put it back on, it worked again like a charm. I was a little worried it was the reason for my flat but I rode 20 more miles on that tube with the light screwed in and 20 more on it without the light since, and it's perfectly fine. I'm taking off one star for the annoyance of assembly and the time it took to get them to work, but overall, for the price, these are pretty awesome lights.!

Seems OK. I needed greater visibility when crossing intersections at night, Or crossing a dark road. Reflectors don't work until you are in the headlights -- they don't warn a driver that there is something to the side moving to where it will be in front.But the patterns won't show unless you are going at a speed you can't achieve when crossing an intersection.-----------------------------------------Update: I bought this a week or so ago with a huge pack of batteries. I feared it would eat thru them. Nope. It is still running strong on the first set. Since I already gave it 5 stars I can't upgrade my evaluation.There WAS a moment of confusion when I tried to screw the first one on and it didn't fit. It has a Presta valve insert threaded into a Schrader valve. Most people will have to unscrew the insert.