Honeywell Home CG510A Thermostat Guard, Small, Fits Thermostats 4.375H x 4.375W inches or Smaller

Small, clear thermostat guard prevents unwanted/unauthorized temperature on your thermostat. Includes built-in lock and key. Fits the following Honeywell thermostat models: CT87, CT3x without the wall plate and the RTH5100B (guard must be removed to access this product's battery door). May fit other thermostats of similar size. Interior dimensions: 4-7/16 W x 4-7/16 H x 2-1/4 D (inches). Outside dimensions: 5-7/8 W x 5-7/8 H x 2-1/2 D (Inch). Includes: cover, base, lock and key, and mounting hardware. 8.8 x 13 x 9.5 inches (Packaged product)