The SRSULT30B is a wireless Bluetooth speaker featuring Powerful bass and clear vocals wherever the party takes you. With a compact design and adjustable shoulder-strap ULT FIELD 3 is a great way to wirelessly enjoy music almost anywhere. Party Connect; wirelessly connect up to 100 compatible speakers together2 Combine 2 ULT FIELD 3 speakers together for wider stereo sound. Sound Field Optimisation ensures music always sounds true-indoors and out Sony Sound Connect app offers 7-Band EQ and other custom settings