There is a BLUETOOTH SPEAKER on the bottom of these!  Take your tunes wherever you need to go...as long as it is in Texas (they might not work in other states...)
 
These 16oz. 4-In-1 Tumblers are amazing!  They come with 2 lids (1 for sipping and 1 for holding a bottle or a "skinny" can), they are insulated to keep the stuff hot or cold, they have a straw, the Bluetooth Speaker that can be unscreed from the bottom, and a charging cord.  What more could you ask for?