The XSM-20 is a 20 pack of magnetic prewire device used to securely bury wire behind a wall or ceiling surface. Accurate to 1/4" through 1" of wood and is re-usable. Xspot mini is designed to work with small gauge wire and/or multiple conductors for anything from speakers, temperature sensors to thermostats. Designed with security applications in mind. Xspot-minis work ve