D.T. Systems designed the H2O 1800 series of electronic training collars specifically for water training. Both the collar and the transmitter are waterproof, and in case you drop it while working your dog in the water, the transmitter floats.
With its PLUS Series, D.T. Systems allows trainers to control up to three dogs with a single transmitter simply by buying additional collars. There are four models in the PLUS Series, each of which offers 16 levels of momentary and continuous stimulation and varying degrees of functions.
CONTACT: D.T. Systems, (214) 350-9446; www.dtsystems.com