There are two distances for each of our models if you have an LBT1 model the distance would be 10M 

Our newer model LBT2 has a 30M range but the 30M range only works if your device has Bluetooth 5.0.

If you have further questions about Bluetooth 5.0 and the range please follow the following link. 

http://support.retrotouch.co.uk/a/solutions/articles/44001875742?lang=en&portalId=44000049250