Dogtra, IQ Plus Remote Dog Trainer, Gently Correct Your Dog With The Low To Medium Output, 400 Yard Range, 2 Hour Rapid Charge Batteries, & A Fully Waterproof, Reduced Size Receiver, Made To Fit Dogs Of Variety Of Sizes, & Can Be Expanded To 2 Dogs With Additional Receiver Collar, Not Included, Long Lasting, Rapid Charge Batteries, Recommended For Small To Medium Sized Dogs.