These are the wireless stereo speakers made from beechwood, the same material used for acoustic guitars. Beechwood’s straight grain and occasional ray fleck yields a birch-like appearance and provides a natural resonance platform for audio. Connecting to any Bluetooth-enabled device, each 4-watt speaker employs True Wireless Stereo technology for a rich sound profile that provides clear trebles and robust bass. Can be used individually or as a pair (required for stereo). They are ideally portable at only 1 1/2" H x 2 1/2" Diam. and weighing only 5 oz. each. Their rechargeable batteries each provide up to six hours of listening from a full charge using their USB AC chargers.