These small devices are great for creating a wireless connection rather than running a long cable, the WT-1 can create a wireless link transmitting a full lossless uncompressed signal for great audio quality.
For ease of use the receiver & sender automatically pair together without the need to pair manually. You can also use these to transmit a single LFE channel for creating a wireless subwoofer link.
Companion receiver model for the WT1 is the WR1 found here.