Temporary Plates. Cooper’s SmartGuard Protection Plates protect electrical work from drywall mud and paint. The reusable plastic covers snap onto common size boxes and can lights; models are available for both empty boxes and ones with devices already installed. The router-resistant plastic also protects wiring from errant cutout tool bits, says the manufacturer. Prices start at 74 cents each when purchased in bulk packs of 50. Cooper Crouse-Hinds, 866/ 764-5454. crouse-hinds.com