It is conveniently small, it can even fit in a pocket. The great advantage is that it has a removable 14500 battery that can be easily replaced, so it allows the battery to be charged in a good external charger, but also to operate for a long period of time with a backup battery. It has a slot for a flat Li Ion 5012XXX battery, but they are not available in Greece. Unfortunately, the battery in the package has a small capacity, 350mAh measured with XTAR, but it is sufficient for 2-3 hours of operation depending on the sound intensity. However, with a good 14500 800mAh battery, this time can be more than doubled. The sound is average but good considering the size of the speaker. The volume is moderate, you won't have a party with it, but for the work I need it for (sea), it is more than enough. The receiver is average but digital. It has a slot for a strap, but there is none in the package. The instructions are inadequate, but the operation is not difficult. It has a annoyingly loud voice in English, similar to that of Chinese boom boxes, which notifies you of the operating mode and persistently about the low battery, but at least it's not in Chinese. It does not display information about the MP3s on the SD card. Very good value for money, I did not try the UDisk feature but I don't think I will need it, so I would give it 5 stars if it had an MP3 menu or hands-free feature.