Nowhere on the box or in the pictures or on the little instruction sheet that I say what Bluetooth version it is. Only in the product description here on the page it mentions at one single time casually Bluetooth 5.3. well hopefully that's actually true. So far I haven't had to do anything to make it reconnect it's reconnected by itself every time. I do a lot of driving and my old one would not connect sometimes just enough to tic me off. My car with the key off all power goes down so I don't have to unplug it or anything like that. I would imagine most cards are like that.It's weird it doesn't mention anywhere in the instructions that holding the main volume button in well shut it off. That's what it does for me if you hold it in a couple seconds. It's nice to have that feature I wish my old one had that. But hopefully I don't have to really use it if it always connects reliably. Not have to unplug my old one a little bit and then plug it back in to repower for it to connect when it decides not to. That was the main reason for upgrading is my old one was Bluetooth 3.0 and it didn't always connect. So far it's doing what I was hoping for. It sounds good and I only hear a little bit of staticky noise when my car volume is literally maxed out. And just a little bit under max. Normal volume I don't even hear anything at all. It goes in snug in the cigarette lighter which is good. I wish I would have a button somewhere to change between blue, green and red led lights or something. That would be able to match most cars as my interior radio lights are a reddish orange. I tried the auxiliary and it worked although the supplied cable doesn't really snap into my phone hardly but it still worked. But it can come out easy so I found a spare that I have in a drawer and have that just in case I want to use it. I haven't tried SD card or the USB function yet. I suppose that would be the way to go to squeeze out the most quality you can with this. With auxiliary hooked up you lose volume knob control and ability to stop a YouTube video. Pressing it once will stop the sound for a YouTube video but not the video itself. It will stop a music player still. My old one did the same thing so I guess it's some kind of hardware compatibility thing going on with auxiliary. I use Bluetooth most of the time anyway and the stop start function works for YouTube videos and music players.So far I'm pretty happy with it and the sound quality is good and it's been reconnecting like a champ which is a big plus for me. Don't forget that if you hold the main volume knob in for a little bit it will shut off. I don't know why that feature is not mentioned anywhere. Holding it in again will turn it back on and it reconnected every time I've done that through just testing. Nice to see the car voltage at all times. Both chargers work just fine although using an app to test the 2.41 seem to always charge slightly faster than the QC 3.0. the most I've seen was 1.6 amps to my phone through the 2.4. and around 1.4 or so with the QC 3.0. Not sure what's going on there but they both work and have sufficient charge. I don't think my old one ever got the ratings it claimed either. You can use Ampere for basic or Accubattery for everything you would ever want to know with your phone battery condition and charging and discharging. This is on Android.

This Guanda RM100 unit performs very well. I am quite familiar with the Bluetooth/FM adapters, having a 2 1/2 yr history with a Roav F2 which I was happy with. But technology marches on and products tend to improve over time. Many of the new generation adapters have the gooseneck that puts the unit within easy reach of your fingers without having to take your eyes off the road - which was the main drawback of the ROAV unit. The Guanda has outstanding sound quality playing MP3's from the U-Drive, and the bluetooth functions pretty much perfectly including hands-free streaming music from your smartphone, sending and receiving calls and voice navigation. I have an 06 Buick with a pretty darned good stock audio system and I am very fussy and hard-to-please about sound quality - the Guanda unit truly impressed me! 2 negatives: (1) there is no off switch so you have to remember to pull the unit out of the cigarette lighter socket if you leave your car sit for an extended period or your battery will end up drained or dead which isn't good for car batteries, and (2) the impressive bouncing "equalizer" bars that superficially look so cool are fake - they actually don't track the music at all. But both of these are minor drawbacks to an otherwise truly outstanding unit. Recommended!

Day one ... Paired quickly and easily via bluetooth. Aux line input worked nicely, worked quite well via a "thumb" drive. The fm communication required turning the volume all the way up, and the sound quality was fair. The line connected sound quality, lack of static, and volume was the best for the inputs, followed by a memory device card/drive blue was good but the fm communication wasn't so hot, I'll have try a few more frequencies to be fair. I will also try the line input with a higher quality (and a bit longer) cable than the one supplied. I have not played with making, or taking calls while driving yet... that's not how I roll. Seems like a pretty good deal at the sale price. I will update with more use.

I have tried these types of devices before, and that was never satisfied with them.This product, however, really exceeded my expectations. I had no trouble pairing my phone with the device. The volume was satisfactory, but the one thing that I especially liked was that I could answer my phone through the car speakers, and it was very clear and it was very easy to do. I just told Siri I wanna make a call to and it did it and it was great. I highly recommend this product. Good quality. The only difficulty is finding and FM station that was very clear. I seem to have too much static, but it didn’t interfere with Enjoying. I had a recommend buying it. Matter of fact I’m gonna buy another one.

I have an old Toyota that continues to amaze me. However, the old stereo in it can only play radio or CD. I've limped along like this for a very long time, but now I can use my smartphone and USB drives to play my tunes. So excited. It worked right out of the box - super easy to set up. Plug it into the cigarette lighter, just find a dead fm station, and tune the device to it and pair your phone with bluetooth. My favorite part is that it obeys my car stereo sound settings, for quality, volume, etc. It has its own volume too very easy to use. Easy to move from one track to the next. Simple, inexpensive solution to a long standing problem, just wish I'd known about it sooner.

Hooks up and works well but the volume seems low.

This model has folder file select function which is important for me because I have a lot of songs in my TF card which requires that function for ease of access . Reception is good and file scoll function has no lag in response. The device also has easy swivel "click" function which is absence in all the previous FM transmitter that I used before.Highly recommend this product

Combines a Bluetooth radio and FM transmitter in a single unit. Works great. Also has a USB port and can charge phones.

El producto funciona muy bien, cumple con lo que dicen las especificaciones

Works very well. I listen to music from Spotify, the music is crystal clear, no interference. more than satisfied. Lars Sweden

Lieferung schnell und alle Funktionen sind fast selbsterklärend zu nutzen. Super Produkt!

Buscaba un reproductor para el coche que no tiene usb, y no quería meter una caratula llamativa para que la roben, en mi caso el coche tiene entrada de audio minijack, con este reproductor se puede conectar por cable evitando al conducir cambiar de emisora, por emisora y bluetooth, tiene equalizador, puedes navegar por las carpetas del usb que conectes y elegir las canciones cómodamente, también se puede acelerar la canción hacia adelante y atrás

excellente