Features:<br /><br />1. Expandable bass resonator・ made of soft silicone material・ easily to stretch or shrink that convenient for carry.<br />2. Hollow objects may be your subwoofer・ you can place the speaker on subwoofer( such as wooden box・ suitcase・ etc.) to enjoy deep bass.<br />3. IPX4 splash-proof・ it perfectly pair with any on-the-go lifestyle.<br />4. Stretch the resonator・ the bass wil enhances 3 times for deep lows.<br />5. 4 mode of ligthing: beat mode・ party mode・ atmosphere mode・ and lamp mode<br />6. It can be attached on the back of phone/tablet to be a phone stand・ it is free to adjust angle.<br />7. Hands-free call. Build-in rechargable battery provides approximately 5 hours working time.<br />8. Suction cup on the bottom enable it can be attached on smooth surfaces.Specifications:General Specification  Brand  ROCK  Model  RAU0520  Color  Gray・ Green  Material  ABS・ metal・ Silicon  Net Weight (g)  170g  Dimensions (cm/ inch)  9.2*9.2*3.5CMTechnical Parameters  Microphone  YES  Connectivity  3.5mm Audio cable + Bluetooth connection  Bluetooth Version  4.1  Transmission Distance  10M  Output Power  4.5W  SNR  75dB  Frequency Response  50-20000Hz  Battery Capacity  600mAh・ 3.7V  Charging Time (h)  Approx. 2 hours  Working Time (h)  5 hours (at 50% of volume)Package  Included:  1* Rock Bluetooth pocket speaker   1* charging cable  1* Manual <br /><br />