i agree with big john, just wanted to add: if thae wall is wood,then your box cannot be set back- it shound be flush. and- if you have that problem with the drywall crumbling,the box will need "mudded around so there isn't more than an 1/8" gap around the perimeter of the device ring per 314.21. also --"caddy" makes a metal piece that looks similar to a madison strap,it goes on when installing the plug. the ears on the plug rest against the metal which has a surface area just slightly smaller than the cover plate. it helps prevent the crumbling problem.
