Internet + Stroller, Viena is a mobile music hall for baby, and combine early learning family nurture into one product. The stroller uses unique sound frequency technique, scientifically control the sound echo through plane wave transmission in order to simulate the real music hall environments. The high definition of true sound quality provides the best grow with me auditory system for baby, also enhance the baby s creativity, language and art potential. By using a super thin pioneer sound oscillator, it could be trickily hide in the stroller canopy and provide unbelievable sound quality. It has Volume control to make the best volume adjustment to baby. 900mAh Environmental protection lithium battery supports 6 hours music play time.