From the RCboatbuild Skunk Works :

"Now enjoy all the thrills of piloting an invisible underwater RC submarine without all the pesky trouble of owning/operating an actual model submarine. Just stand on the shore with the RC Super Saver Submarine remote transmitter in your hands and experience all the thrills of driving an invisible RC model sub just as if there is one somewhere out of sight ! "

The Complete RC Super Saver Submarine Kit : (batteries not included)