How it works: 
Simply plug in your analog audio source into the RCA jacks, then connect your digital receiving device to your choice of either coaxial or optical digital output.
Both digital outputs may also be used simultaneously. Power-cycle all connected equipment, and you will be enjoying digitally converted audio from your analog source at the receiving device.
The digital output signals will be a 2 channel uncompressed LPCM (linear pulse code modulation) with sampling rate at 48KHz. 

Specifications: 
Coaxial and optical output ports
Right and Left RCA Stereo input ports
100-240VAC to 5VDC power supply (US/EU standards, CE/FCC/UL certified)
Dimensions: 1.65" W x 0.87" H x 1.59" D
Weight: 25g (unit only)
Black metal chassis
Operating temperature: 0-70 deg. C 

Package Includes: 1 x Analog Stereo to Digital Optical Coax Audio Converter, 1 x Power Adapter(supply:110V~240V), 1 x U