505 Robertshaw Series Builder Mechanical Thermostat The Braeburn® 505 Megaswitch Mechanical Thermostat technology is tested for long switch life. Heavy duty ball-type system and fan switchesEnvironmentally safe - mercury free, front mounted wiring terminals, heavy duty anticipatorIntegrated sub-base for easy installationElectro-plated wiring terminals to help prevent corrosionNo leveling required during installationSystem Lever OFF/HEATFree contractor branding available