here's a link to the plug in,
http://www.drsfostersmith.com/produc...m?pcatid=13043

Instead of the shock collar, (where any noise can set it off and can shock the dog for no reason) Why not try a Citronella collar?

http://www.muttmart.com/CitronellaBa...FRTWJAod209TbQ

Do you leave a radio/Tv on when your gone?
I hide treats all around my house when I'm gone to keep my dogs from going crazy.