SINOBAND S400 Waterproof, Dustproof and Shockproof Portable Stereo Power Bank Bluetooth Speaker in Black, Bluetooth CSR 4.0, with FREE Quality Custom Made Pouch Carry Case, Compatible with Smartphone, Tablets, and Other Bluetooth- Capable Devices, Super Bass Releases Hi-fi Sound, Powerful 7000mAh Polymer Lithium Battery.

The audio quality of this speaker is really good for its size and price range. It is easy to pair. It actually is the first bluetooth speaker that I have been able to get to pair and have no dropped signal from my 2010 MacBook Pro. Even my Jabra Solemate wouldn't. While these are great the most fantastic aspect is the extremely long battery life. I wouldn't believe how long it is if I weren't the one testing it. I charged it fully and started playing music through on Thursday about 8pm. It is now Monday and it is still playing. I haven't charged it even a little bit nor have I turned it off since Thursday. Much of that time has been running audio via Bluetooth but did switch it out for 1/8 TRS (headphone) input for a while. I don't know how long it will run but will post when the battery goes dead.The battery officially died after running continuously for 140 hours 26 minutes. Marathon battery life!

This thing is awesome. I've owned several bluetooth speakers and this one is by far my favorite. Water and dust resistant, the battery lasts a RIDICULOUSLY long time, and it can charge your phone battery!! I think it took a month before I ran the battery down the first time. I take this on hiking trips to keep my phone charge, out to the park when I play fetch with my dog and everywhere else. I once dropped this in Caddo River in Arkansas on a fly fishing trip and it kept on trucking. My only regret is that I didn't buy one of these sooner.That being said, bluetooth speakers always degrade the sound quality because of how they work. If you've obsessing over audio quality you should never use wireless speakers. I'm an electrical engineer and worked with a lot of audio equipment and this thing is great. Sounds great for bluetooth, easy to use, nice and loud and super inexpensive.

I've done some light testing of the speaker so far. It has a good weight and is easy to hold in the hand, making it fun to carry around the house. The rubber trim along the outside is textured with small bumps which feel good in the hand and shows the quality of the rubber well.It's well balanced and can easily stand despite the narrow looking base. It also sits really well vertically, using the battery pack cover as a base. In fact, I lightly pushed it a few times with my finger and it was able to remain standing.The two 3 Watt speakers sound clear, loud, full, and also provide a little kick of bass, which was important to me when looking for a speaker. Even at lower volumes there's a feeling of bass.My ONLY critique, not even a complaint, is that the broken english directions don't make clear that you need to hold the power button for a good 2 seconds (an eternity nowadays) to turn it on and off. That wasn't enough to reduce my rating though. Everything about it has been great.

This speaker has the best sound and bass of any I've owned. It's heave and well made and for under $200 it's amazing! The only reason I did not give it 5 starts is that it uses a standard USB to USB (NOT a USB to Micro USB like just about everything else) to charge it. Thankfully it comes with one, because who has a USB to USB cable laying around? It would have been much better if we could have all used our phone chargers to power this speaker...maybe in the second release they'll get this right? But USB to USB cables are readily available, so don't let this hold you back in buying this speaker, its a great product, you won't be disappointed!

This is probably the best online purchase I have ever made! The sound is great, the bass isn't too in your face or non existent, and the sound doesn't distort when turned up. I have personally tested this product under running water and found it to be water resistant as advertised. I'm considering getting more for gifts!UPDATE: We have owned this product for little over a year now, and the battery is now terrible. Charging it takes longer and doesn't last anywhere near as long. Every time we want to use it (which is less frequently due to this), the battery is always dead and we end up just using our phones instead. We took incredibly good care of the product: did not charge it until it died to preserve the battery, never submerged under water, very few falls from high places, stored properly, etc. The sound is still great and the bass has no distortion. After a single year of using this product, I would rate this as 3 stars. The battery life was, after all, the main selling feature for this product.

The speaker worked extremely well this weekend all the way up to the point where I knocked it into the river. I took it on our overnight Kayaking Adventure. Even in the pouring rain and the beating sun it worked flawlessly and after 6 hours of continuous use it still appeared to have almost a full charge. I like it so much that I immediately ordered a second one. If only the unit floated, perhaps I could have found it and tested it further. I will be leashing the new one as soon as it arrives. My only complaint is that it's not submersible. If they come out with one like that I would buy it.

Feels solidly built and puts out great sound for its size. The only issue for mine is the audio input jack seems finicky---I have to fiddle with the connection to make it work sometimes. Bluetooth connection has been excellent, but the range is limited to about 10-15 feet unless you don't mind skips and signal drop-offs.The quirks aren't deal-breakers for me, it's still really good sound for the money. But thought it would be nice if you know the limitations before making a decision.

This bluetooth speaker has got to have the longest battery life I've ever seen! It came to me fully charged and I have used this speaker at least 10 - 12 hrs and it still indicates a full battery! I have not charged this speaker since I've received it! Amazing sound, easy connect and a compact design, combined with the large capacity battery makes this a must-have item for those of you interested in electronic gadgets!