Sanyun SW228BT Powered Bluetooth Bookshelf Speakers - 4 Inch Active Carbon Fiber Speaker- Wireless Studio Monitors - Optical RCA 3.5mm Audio Inputs - 46W RMS - Wooden Enclosure 

Superb HiFi Bookshelf speakers 

4-inch carbon fiber speaker an 52mm silk dome

Bluetooth and Wired Dual Modes

Remote Control

Volume, Treble and Bass Control

Quiet standby and energy saving

Output power(RMS): 23W x 2

Speaker unit: ( 4+2)" x 2

Impedance: 7 ohm

Input sensitivity: 600±50mV

S/N ratio: >85dB

Frequency response range: 40Hz to 20KHz

THD+N: ≤2% at maximum volume output

Interface: Bluetooth mode and optical/RCA and 3.5mm AUX inputs.

Power supply: AC 100-240V  50/60Hz