Are they rechargeable or what is the USB cable for?
763471
They are rechargeable. The USB is to connect the glasses to a USB port in your computer.I found the recharging to be cumbersome time consuming, approx. 2 hours per set of glasses. I prefer 3D glasses w/batteries.
1473576
They have a USB cable to charge them, but they only work Bluetooth. They are pretty large, so I am not sure they would be a good choice for a phone. I have a different set that I use with my phone. I bought these a year ago and they work great. http://www.amazon.com/gp/product/B00EDPW2Q8/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc;=1 I am very happy with them. Again, Bluetooth only, USB cable to charge.
1296247
Yes. That is mainly what I use them for. After recharging; they work as well as a new battery.
1212966
Recharges by USB. Which, ironically, is the same way it charges other things... Basically, if you have the ability to recharge it, you probably do not need it right then.
785989
i can't tell you, but Ive had no trouble with them. I've recharged these several times. They work well.
380475
They are powered by an AC adapter via electric outlet. USB just doesn't have the power to push out good sound in most cases.
791773
Littuim and they are rechargeable. Our staff takes lots of photos daily I buy an extra battery and they switch the out daily and this allows us to keep battery life longer and utilize cameras daily.
536282
They are not rechargeable. You have to take the center two pieces apart take out the piece in the center out and use a small Phillips head screwdriver to remove the battery cover to replace them.
226498
It is rechargeable by USB. Not sure about battery because I don't use it much so haven't looked for a battery to change.
630055
There is a usb cable that you can plug in a computer to charge the batteries
558260
No problem, they are recharged via a USB port. The only problem I've had with Bluetooth operation is with the small portable Bluetooth transmitter, I've gone through 5 already, non have lasted more then 3 months Fritz
941911
They come with very short, rather worthless, USB cables. Since I have so many chargers for phones, Kindle, etc that are longer, I just charge them using those. Yes, you could leave them plugged in while using them.
227134
I use them alot , most of the day in fact, and I can get around 5 hours (talking on Skype and listening to Youtube videos) of use out of them before they need recharged. They take about a hour to recharge ( I just use them with the charging cord plugged in)
884779
I haven't used them enough to know; they tend to sit around so the charge does deplete over time. However, they recharge quickly so I am not concerned if they last long or not as I have 2. Pat
61598
You can keep them in the charger when not using them. Or, at least I do and they still work!
425859
You can recharge them at any time. I bought from Barbjewels and received a no name version instead of the Fuji pictured. Completely dead and unchargeable- the hassel of returning it eventually turned me off-beware!
350798
The glasses do not come with a USB cable and are not rechargeable. They do take small lithium batteries and you get about 5 batteries for each pair of glasses.To date, we have not had to replace any batteries and we've had the glasses for about a year and a half. Also, you only need to have the glasses on when yourwatching a program in 3D. I hope this helps.