This signal is the most modern. A language made up of 1's and 0's and encoded in a way that nothing else can interfere with.

Just like your phone and your wifi router or modern baby monitor, its a special language and you wont have to worry about anything effecting how it works.

Its the signal used by Invisible Fence. 

This brand is the premium brand of all these systems. Its small, lightweight and  fast to respond to the signal. 

Many cat owners go for this brand because of its size and weight being so small.

Its not cheap -  its the best money can buy.