I've tried other less expensive bark control devices without success. Dog Silencer MAX is the most expensive one I've tried and most importantly, the only one that actually works GREAT. I guess you get what you pay for. Trying other models, some required me to change the battery every 2 days. Others didn't seem to work or you couldn't tell if they were even emitting a high frequency sound. One model I tried claimed the battery lasted for 30 days but it was actually only about 3 days. Well, Dog Silencer MAX has solved all these problems: It has an optional 60ft electric cable that allows you to plug the device into an outlet and never needs batteries. It has a remote control pushbutton device that gives me great satisfaction to manually press when I hear a dog barking. (It also has automatic bark detection, but there is something very satisfying to actually pressing the manual button). And finally, there is a switch option I irregularly use that turns on a tone that a human can actually hear and I use this tone to check to make sure the device is actually working. So, in summary, this might be the most expensive device on the market, but it's worth every penny.